]> Cypherpunks.ru repositories - nncp.git/blobdiff - src/sp.go
Raise copyright years
[nncp.git] / src / sp.go
index 580b97efb725c6024c80321196164393afbc2b15..4db358742a17b1f584aa102ac853a1c6386c6d13 100644 (file)
--- a/src/sp.go
+++ b/src/sp.go
@@ -1,6 +1,6 @@
 /*
 NNCP -- Node to Node copy, utilities for store-and-forward data exchange
-Copyright (C) 2016-2020 Sergey Matveev <stargrave@stargrave.org>
+Copyright (C) 2016-2022 Sergey Matveev <stargrave@stargrave.org>
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -21,8 +21,9 @@ import (
        "bytes"
        "crypto/subtle"
        "errors"
+       "fmt"
        "io"
-       "net"
+       "log"
        "os"
        "path/filepath"
        "sort"
@@ -30,24 +31,34 @@ import (
        "time"
 
        xdr "github.com/davecgh/go-xdr/xdr2"
+       "github.com/dustin/go-humanize"
        "github.com/flynn/noise"
 )
 
 const (
-       MaxSPSize       = 1<<16 - 256
-       PartSuffix      = ".part"
-       DefaultDeadline = 10
-
-       SPHeadOverhead  = 4
+       MaxSPSize      = 1<<16 - 256
+       PartSuffix     = ".part"
+       SPHeadOverhead = 4
 )
 
-var (
-       MagicNNCPLv1 [8]byte = [8]byte{'N', 'N', 'C', 'P', 'S', 0, 0, 1}
+type MTHAndOffset struct {
+       mth    MTH
+       offset uint64
+}
+
+type SPCheckerTask struct {
+       nodeId *NodeId
+       hsh    *[MTHSize]byte
+       mth    MTH
+       done   chan []byte
+}
 
+var (
        SPInfoOverhead    int
        SPFreqOverhead    int
        SPFileOverhead    int
        SPHaltMarshalized []byte
+       SPPingMarshalized []byte
 
        NoiseCipherSuite noise.CipherSuite = noise.NewCipherSuite(
                noise.DH25519,
@@ -55,9 +66,19 @@ var (
                noise.HashBLAKE2b,
        )
 
-       spWorkersGroup sync.WaitGroup
+       DefaultDeadline = 10 * time.Second
+       PingTimeout     = time.Minute
+
+       spCheckerTasks chan SPCheckerTask
+       SPCheckerWg    sync.WaitGroup
+       spCheckerOnce  sync.Once
 )
 
+type FdAndFullSize struct {
+       fd       *os.File
+       fullSize int64
+}
+
 type SPType uint8
 
 const (
@@ -66,6 +87,7 @@ const (
        SPTypeFile SPType = iota
        SPTypeDone SPType = iota
        SPTypeHalt SPType = iota
+       SPTypePing SPType = iota
 )
 
 type SPHead struct {
@@ -75,22 +97,22 @@ type SPHead struct {
 type SPInfo struct {
        Nice uint8
        Size uint64
-       Hash *[32]byte
+       Hash *[MTHSize]byte
 }
 
 type SPFreq struct {
-       Hash   *[32]byte
+       Hash   *[MTHSize]byte
        Offset uint64
 }
 
 type SPFile struct {
-       Hash    *[32]byte
+       Hash    *[MTHSize]byte
        Offset  uint64
        Payload []byte
 }
 
 type SPDone struct {
-       Hash *[32]byte
+       Hash *[MTHSize]byte
 }
 
 type SPRaw struct {
@@ -119,34 +141,42 @@ func init() {
        copy(SPHaltMarshalized, buf.Bytes())
        buf.Reset()
 
-       spInfo := SPInfo{Nice: 123, Size: 123, Hash: new([32]byte)}
+       spHead = SPHead{Type: SPTypePing}
+       if _, err := xdr.Marshal(&buf, spHead); err != nil {
+               panic(err)
+       }
+       SPPingMarshalized = make([]byte, SPHeadOverhead)
+       copy(SPPingMarshalized, buf.Bytes())
+       buf.Reset()
+
+       spInfo := SPInfo{Nice: 123, Size: 123, Hash: new([MTHSize]byte)}
        if _, err := xdr.Marshal(&buf, spInfo); err != nil {
                panic(err)
        }
        SPInfoOverhead = buf.Len()
        buf.Reset()
 
-       spFreq := SPFreq{Hash: new([32]byte), Offset: 123}
+       spFreq := SPFreq{Hash: new([MTHSize]byte), Offset: 123}
        if _, err := xdr.Marshal(&buf, spFreq); err != nil {
                panic(err)
        }
        SPFreqOverhead = buf.Len()
        buf.Reset()
 
-       spFile := SPFile{Hash: new([32]byte), Offset: 123}
+       spFile := SPFile{Hash: new([MTHSize]byte), Offset: 123}
        if _, err := xdr.Marshal(&buf, spFile); err != nil {
                panic(err)
        }
        SPFileOverhead = buf.Len()
+       spCheckerTasks = make(chan SPCheckerTask)
 }
 
 func MarshalSP(typ SPType, sp interface{}) []byte {
        var buf bytes.Buffer
-       var err error
-       if _, err = xdr.Marshal(&buf, SPHead{typ}); err != nil {
+       if _, err := xdr.Marshal(&buf, SPHead{typ}); err != nil {
                panic(err)
        }
-       if _, err = xdr.Marshal(&buf, sp); err != nil {
+       if _, err := xdr.Marshal(&buf, sp); err != nil {
                panic(err)
        }
        return buf.Bytes()
@@ -172,21 +202,26 @@ type SPState struct {
        Ctx            *Ctx
        Node           *Node
        Nice           uint8
-       onlineDeadline uint
-       maxOnlineTime  uint
+       NoCK           bool
+       onlineDeadline time.Duration
+       maxOnlineTime  time.Duration
        hs             *noise.HandshakeState
        csOur          *noise.CipherState
        csTheir        *noise.CipherState
        payloads       chan []byte
-       infosTheir     map[[32]byte]*SPInfo
-       infosOurSeen   map[[32]byte]uint8
+       pings          chan struct{}
+       infosTheir     map[[MTHSize]byte]*SPInfo
+       infosOurSeen   map[[MTHSize]byte]uint8
        queueTheir     []*FreqWithNice
        wg             sync.WaitGroup
        RxBytes        int64
        RxLastSeen     time.Time
+       RxLastNonPing  time.Time
        TxBytes        int64
        TxLastSeen     time.Time
+       TxLastNonPing  time.Time
        started        time.Time
+       mustFinishAt   time.Time
        Duration       time.Duration
        RxSpeed        int64
        TxSpeed        int64
@@ -195,22 +230,44 @@ type SPState struct {
        xxOnly         TRxTx
        rxRate         int
        txRate         int
-       isDead         bool
+       isDead         chan struct{}
        listOnly       bool
-       onlyPkts       map[[32]byte]bool
+       onlyPkts       map[[MTHSize]byte]bool
+       writeSPBuf     bytes.Buffer
+       fds            map[string]FdAndFullSize
+       fdsLock        sync.RWMutex
+       fileHashers    map[string]*MTHAndOffset
+       progressBars   map[string]struct{}
        sync.RWMutex
 }
 
-func (state *SPState) NotAlive() bool {
-       if state.isDead {
-               return true
+func (state *SPState) SetDead() {
+       state.Lock()
+       defer state.Unlock()
+       select {
+       case <-state.isDead:
+               // Already closed channel, dead
+               return
+       default:
        }
-       now := time.Now()
-       if state.maxOnlineTime > 0 && state.started.Add(time.Duration(state.maxOnlineTime)*time.Second).Before(now) {
+       close(state.isDead)
+       go func() {
+               for range state.payloads {
+               }
+       }()
+       go func() {
+               for range state.pings {
+               }
+       }()
+}
+
+func (state *SPState) NotAlive() bool {
+       select {
+       case <-state.isDead:
                return true
+       default:
        }
-       return uint(now.Sub(state.RxLastSeen).Seconds()) >= state.onlineDeadline &&
-               uint(now.Sub(state.TxLastSeen).Seconds()) >= state.onlineDeadline
+       return false
 }
 
 func (state *SPState) dirUnlock() {
@@ -218,11 +275,21 @@ func (state *SPState) dirUnlock() {
        state.Ctx.UnlockDir(state.txLock)
 }
 
-func (state *SPState) WriteSP(dst io.Writer, payload []byte) error {
-       n, err := xdr.Marshal(dst, SPRaw{Magic: MagicNNCPLv1, Payload: payload})
-       if err == nil {
+func (state *SPState) WriteSP(dst io.Writer, payload []byte, ping bool) error {
+       state.writeSPBuf.Reset()
+       n, err := xdr.Marshal(&state.writeSPBuf, SPRaw{
+               Magic:   MagicNNCPSv1.B,
+               Payload: payload,
+       })
+       if err != nil {
+               return err
+       }
+       if n, err = dst.Write(state.writeSPBuf.Bytes()); err == nil {
                state.TxLastSeen = time.Now()
                state.TxBytes += int64(n)
+               if !ping {
+                       state.TxLastNonPing = state.TxLastSeen
+               }
        }
        return err
 }
@@ -239,17 +306,16 @@ func (state *SPState) ReadSP(src io.Reader) ([]byte, error) {
        }
        state.RxLastSeen = time.Now()
        state.RxBytes += int64(n)
-       if sp.Magic != MagicNNCPLv1 {
+       if sp.Magic != MagicNNCPSv1.B {
                return nil, BadMagic
        }
        return sp.Payload, nil
 }
 
-func (ctx *Ctx) infosOur(nodeId *NodeId, nice uint8, seen *map[[32]byte]uint8) [][]byte {
+func (ctx *Ctx) infosOur(nodeId *NodeId, nice uint8, seen *map[[MTHSize]byte]uint8) [][]byte {
        var infos []*SPInfo
        var totalSize int64
        for job := range ctx.Jobs(nodeId, TTx) {
-               job.Fd.Close()
                if job.PktEnc.Nice > nice {
                        continue
                }
@@ -268,19 +334,34 @@ func (ctx *Ctx) infosOur(nodeId *NodeId, nice uint8, seen *map[[32]byte]uint8) [
        var payloads [][]byte
        for _, info := range infos {
                payloads = append(payloads, MarshalSP(SPTypeInfo, info))
-               ctx.LogD("sp-info-our", SDS{
-                       "node": nodeId,
-                       "name": ToBase32(info.Hash[:]),
-                       "size": info.Size,
-               }, "")
+               pktName := Base32Codec.EncodeToString(info.Hash[:])
+               ctx.LogD("sp-info-our", LEs{
+                       {"Node", nodeId},
+                       {"Name", pktName},
+                       {"Size", info.Size},
+               }, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "Our info: %s/tx/%s (%s)",
+                               ctx.NodeName(nodeId),
+                               pktName,
+                               humanize.IBytes(info.Size),
+                       )
+               })
        }
        if totalSize > 0 {
-               ctx.LogI("sp-infos", SDS{
-                       "xx":   string(TTx),
-                       "node": nodeId,
-                       "pkts": len(payloads),
-                       "size": totalSize,
-               }, "")
+               ctx.LogI("sp-infos-tx", LEs{
+                       {"XX", string(TTx)},
+                       {"Node", nodeId},
+                       {"Pkts", len(payloads)},
+                       {"Size", totalSize},
+               }, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "We have got for %s: %d packets, %s",
+                               ctx.NodeName(nodeId),
+                               len(payloads),
+                               humanize.IBytes(uint64(totalSize)),
+                       )
+               })
        }
        return payloadsSplit(payloads)
 }
@@ -293,14 +374,14 @@ func (state *SPState) StartI(conn ConnDeadlined) error {
        }
        var rxLock *os.File
        if !state.listOnly && (state.xxOnly == "" || state.xxOnly == TRx) {
-               rxLock, err = state.Ctx.LockDir(nodeId, TRx)
+               rxLock, err = state.Ctx.LockDir(nodeId, string(TRx))
                if err != nil {
                        return err
                }
        }
        var txLock *os.File
        if !state.listOnly && (state.xxOnly == "" || state.xxOnly == TTx) {
-               txLock, err = state.Ctx.LockDir(nodeId, TTx)
+               txLock, err = state.Ctx.LockDir(nodeId, string(TTx))
                if err != nil {
                        return err
                }
@@ -322,8 +403,10 @@ func (state *SPState) StartI(conn ConnDeadlined) error {
        }
        state.hs = hs
        state.payloads = make(chan []byte)
-       state.infosTheir = make(map[[32]byte]*SPInfo)
-       state.infosOurSeen = make(map[[32]byte]uint8)
+       state.pings = make(chan struct{})
+       state.infosTheir = make(map[[MTHSize]byte]*SPInfo)
+       state.infosOurSeen = make(map[[MTHSize]byte]uint8)
+       state.progressBars = make(map[string]struct{})
        state.started = started
        state.rxLock = rxLock
        state.txLock = txLock
@@ -348,31 +431,73 @@ func (state *SPState) StartI(conn ConnDeadlined) error {
                state.dirUnlock()
                return err
        }
-       sds := SDS{"node": nodeId, "nice": int(state.Nice)}
-       state.Ctx.LogD("sp-start", sds, "sending first message")
-       conn.SetWriteDeadline(time.Now().Add(DefaultDeadline * time.Second))
-       if err = state.WriteSP(conn, buf); err != nil {
-               state.Ctx.LogE("sp-start", sds, err, "")
+       les := LEs{{"Node", nodeId}, {"Nice", int(state.Nice)}}
+       state.Ctx.LogD("sp-startI", les, func(les LEs) string {
+               return fmt.Sprintf(
+                       "SP with %s (nice %s): sending first message",
+                       state.Node.Name,
+                       NicenessFmt(state.Nice),
+               )
+       })
+       conn.SetWriteDeadline(time.Now().Add(DefaultDeadline))
+       if err = state.WriteSP(conn, buf, false); err != nil {
+               state.Ctx.LogE("sp-startI", les, err, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "SP with %s (nice %s): writing",
+                               state.Node.Name,
+                               NicenessFmt(state.Nice),
+                       )
+               })
                state.dirUnlock()
                return err
        }
-       state.Ctx.LogD("sp-start", sds, "waiting for first message")
-       conn.SetReadDeadline(time.Now().Add(DefaultDeadline * time.Second))
+       state.Ctx.LogD("sp-startI-wait", les, func(les LEs) string {
+               return fmt.Sprintf(
+                       "SP with %s (nice %s): waiting for first message",
+                       state.Node.Name,
+                       NicenessFmt(state.Nice),
+               )
+       })
+       conn.SetReadDeadline(time.Now().Add(DefaultDeadline))
        if buf, err = state.ReadSP(conn); err != nil {
-               state.Ctx.LogE("sp-start", sds, err, "")
+               state.Ctx.LogE("sp-startI-read", les, err, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "SP with %s (nice %s): reading",
+                               state.Node.Name,
+                               NicenessFmt(state.Nice),
+                       )
+               })
                state.dirUnlock()
                return err
        }
        payload, state.csOur, state.csTheir, err = state.hs.ReadMessage(nil, buf)
        if err != nil {
-               state.Ctx.LogE("sp-start", sds, err, "")
+               state.Ctx.LogE("sp-startI-read", les, err, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "SP with %s (nice %s): reading Noise message",
+                               state.Node.Name,
+                               NicenessFmt(state.Nice),
+                       )
+               })
                state.dirUnlock()
                return err
        }
-       state.Ctx.LogD("sp-start", sds, "starting workers")
+       state.Ctx.LogD("sp-startI-workers", les, func(les LEs) string {
+               return fmt.Sprintf(
+                       "SP with %s (nice %s): starting workers",
+                       state.Node.Name,
+                       NicenessFmt(state.Nice),
+               )
+       })
        err = state.StartWorkers(conn, infosPayloads, payload)
        if err != nil {
-               state.Ctx.LogE("sp-start", sds, err, "")
+               state.Ctx.LogE("sp-startI-workers", les, err, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "SP with %s (nice %s): starting workers",
+                               state.Node.Name,
+                               NicenessFmt(state.Nice),
+                       )
+               })
                state.dirUnlock()
        }
        return err
@@ -396,48 +521,62 @@ func (state *SPState) StartR(conn ConnDeadlined) error {
        xxOnly := TRxTx("")
        state.hs = hs
        state.payloads = make(chan []byte)
-       state.infosOurSeen = make(map[[32]byte]uint8)
-       state.infosTheir = make(map[[32]byte]*SPInfo)
+       state.pings = make(chan struct{})
+       state.infosOurSeen = make(map[[MTHSize]byte]uint8)
+       state.infosTheir = make(map[[MTHSize]byte]*SPInfo)
+       state.progressBars = make(map[string]struct{})
        state.started = started
        state.xxOnly = xxOnly
+
        var buf []byte
        var payload []byte
-       state.Ctx.LogD("sp-start", SDS{"nice": int(state.Nice)}, "waiting for first message")
-       conn.SetReadDeadline(time.Now().Add(DefaultDeadline * time.Second))
+       logMsg := func(les LEs) string {
+               return fmt.Sprintf(
+                       "SP nice %s: waiting for first message",
+                       NicenessFmt(state.Nice),
+               )
+       }
+       les := LEs{{"Nice", int(state.Nice)}}
+       state.Ctx.LogD("sp-startR", les, logMsg)
+       conn.SetReadDeadline(time.Now().Add(DefaultDeadline))
        if buf, err = state.ReadSP(conn); err != nil {
-               state.Ctx.LogE("sp-start", SDS{}, err, "")
+               state.Ctx.LogE("sp-startR-read", les, err, logMsg)
                return err
        }
        if payload, _, _, err = state.hs.ReadMessage(nil, buf); err != nil {
-               state.Ctx.LogE("sp-start", SDS{}, err, "")
+               state.Ctx.LogE("sp-startR-read", les, err, logMsg)
                return err
        }
 
        var node *Node
        for _, n := range state.Ctx.Neigh {
+               if n.NoisePub == nil {
+                       continue
+               }
                if subtle.ConstantTimeCompare(state.hs.PeerStatic(), n.NoisePub[:]) == 1 {
                        node = n
                        break
                }
        }
        if node == nil {
-               peerId := ToBase32(state.hs.PeerStatic())
-               state.Ctx.LogE("sp-start", SDS{"peer": peerId}, errors.New("unknown"), "")
-               return errors.New("Unknown peer: " + peerId)
+               peerId := Base32Codec.EncodeToString(state.hs.PeerStatic())
+               err = errors.New("unknown peer: " + peerId)
+               state.Ctx.LogE("sp-startR-unknown", append(les, LE{"Peer", peerId}), err, logMsg)
+               return err
        }
        state.Node = node
        state.rxRate = node.RxRate
        state.txRate = node.TxRate
        state.onlineDeadline = node.OnlineDeadline
        state.maxOnlineTime = node.MaxOnlineTime
-       sds := SDS{"node": node.Id, "nice": int(state.Nice)}
+       les = LEs{{"Node", node.Id}, {"Nice", int(state.Nice)}}
 
-       if state.Ctx.ensureRxDir(node.Id); err != nil {
+       if err = state.Ctx.ensureRxDir(node.Id); err != nil {
                return err
        }
        var rxLock *os.File
        if xxOnly == "" || xxOnly == TRx {
-               rxLock, err = state.Ctx.LockDir(node.Id, TRx)
+               rxLock, err = state.Ctx.LockDir(node.Id, string(TRx))
                if err != nil {
                        return err
                }
@@ -445,7 +584,7 @@ func (state *SPState) StartR(conn ConnDeadlined) error {
        state.rxLock = rxLock
        var txLock *os.File
        if xxOnly == "" || xxOnly == TTx {
-               txLock, err = state.Ctx.LockDir(node.Id, TTx)
+               txLock, err = state.Ctx.LockDir(node.Id, string(TTx))
                if err != nil {
                        return err
                }
@@ -465,19 +604,34 @@ func (state *SPState) StartR(conn ConnDeadlined) error {
                firstPayload = append(firstPayload, SPHaltMarshalized...)
        }
 
-       state.Ctx.LogD("sp-start", sds, "sending first message")
+       state.Ctx.LogD("sp-startR-write", les, func(les LEs) string {
+               return fmt.Sprintf(
+                       "SP with %s (nice %s): sending first message",
+                       node.Name, NicenessFmt(state.Nice),
+               )
+       })
        buf, state.csTheir, state.csOur, err = state.hs.WriteMessage(nil, firstPayload)
        if err != nil {
                state.dirUnlock()
                return err
        }
-       conn.SetWriteDeadline(time.Now().Add(DefaultDeadline * time.Second))
-       if err = state.WriteSP(conn, buf); err != nil {
-               state.Ctx.LogE("sp-start", sds, err, "")
+       conn.SetWriteDeadline(time.Now().Add(DefaultDeadline))
+       if err = state.WriteSP(conn, buf, false); err != nil {
+               state.Ctx.LogE("sp-startR-write", les, err, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "SP with %s (nice %s): writing",
+                               node.Name, NicenessFmt(state.Nice),
+                       )
+               })
                state.dirUnlock()
                return err
        }
-       state.Ctx.LogD("sp-start", sds, "starting workers")
+       state.Ctx.LogD("sp-startR-workers", les, func(les LEs) string {
+               return fmt.Sprintf(
+                       "SP with %s (nice %s): starting workers",
+                       node.Name, NicenessFmt(state.Nice),
+               )
+       })
        err = state.StartWorkers(conn, infosPayloads, payload)
        if err != nil {
                state.dirUnlock()
@@ -485,88 +639,214 @@ func (state *SPState) StartR(conn ConnDeadlined) error {
        return err
 }
 
+func (state *SPState) closeFd(pth string) {
+       state.fdsLock.Lock()
+       if s, exists := state.fds[pth]; exists {
+               delete(state.fds, pth)
+               s.fd.Close()
+       }
+       state.fdsLock.Unlock()
+}
+
 func (state *SPState) StartWorkers(
        conn ConnDeadlined,
        infosPayloads [][]byte,
-       payload []byte) error {
-       sds := SDS{"node": state.Node.Id, "nice": int(state.Nice)}
+       payload []byte,
+) error {
+       les := LEs{{"Node", state.Node.Id}, {"Nice", int(state.Nice)}}
+       state.fds = make(map[string]FdAndFullSize)
+       state.fileHashers = make(map[string]*MTHAndOffset)
+       state.isDead = make(chan struct{})
+       if state.maxOnlineTime > 0 {
+               state.mustFinishAt = state.started.Add(state.maxOnlineTime)
+       }
+       if !state.NoCK {
+               spCheckerOnce.Do(func() { go SPChecker(state.Ctx) })
+               go func() {
+                       for job := range state.Ctx.JobsNoCK(state.Node.Id) {
+                               if job.PktEnc.Nice <= state.Nice {
+                                       spCheckerTasks <- SPCheckerTask{
+                                               nodeId: state.Node.Id,
+                                               hsh:    job.HshValue,
+                                               done:   state.payloads,
+                                       }
+                               }
+                       }
+               }()
+       }
+
+       // Remaining handshake payload sending
        if len(infosPayloads) > 1 {
+               state.wg.Add(1)
                go func() {
                        for _, payload := range infosPayloads[1:] {
                                state.Ctx.LogD(
-                                       "sp-work",
-                                       SdsAdd(sds, SDS{"size": len(payload)}),
-                                       "queuing remaining payload",
+                                       "sp-queue-remaining",
+                                       append(les, LE{"Size", int64(len(payload))}),
+                                       func(les LEs) string {
+                                               return fmt.Sprintf(
+                                                       "SP with %s (nice %s): queuing remaining payload (%s)",
+                                                       state.Node.Name, NicenessFmt(state.Nice),
+                                                       humanize.IBytes(uint64(len(payload))),
+                                               )
+                                       },
                                )
                                state.payloads <- payload
                        }
+                       state.wg.Done()
                }()
        }
-       state.Ctx.LogD(
-               "sp-work",
-               SdsAdd(sds, SDS{"size": len(payload)}),
-               "processing first payload",
-       )
+
+       // Processing of first payload and queueing its responses
+       logMsg := func(les LEs) string {
+               return fmt.Sprintf(
+                       "SP with %s (nice %s): processing first payload (%s)",
+                       state.Node.Name, NicenessFmt(state.Nice),
+                       humanize.IBytes(uint64(len(payload))),
+               )
+       }
+       state.Ctx.LogD("sp-process", append(les, LE{"Size", int64(len(payload))}), logMsg)
        replies, err := state.ProcessSP(payload)
        if err != nil {
-               state.Ctx.LogE("sp-work", sds, err, "")
+               state.Ctx.LogE("sp-process", les, err, logMsg)
                return err
        }
-
+       state.wg.Add(1)
        go func() {
                for _, reply := range replies {
                        state.Ctx.LogD(
-                               "sp-work",
-                               SdsAdd(sds, SDS{"size": len(reply)}),
-                               "queuing reply",
+                               "sp-queue-reply",
+                               append(les, LE{"Size", int64(len(reply))}),
+                               func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): queuing reply (%s)",
+                                               state.Node.Name, NicenessFmt(state.Nice),
+                                               humanize.IBytes(uint64(len(payload))),
+                                       )
+                               },
                        )
                        state.payloads <- reply
                }
+               state.wg.Done()
        }()
 
+       // Periodic jobs
+       state.wg.Add(1)
+       go func() {
+               deadlineTicker := time.NewTicker(time.Second)
+               pingTicker := time.NewTicker(PingTimeout)
+               for {
+                       select {
+                       case <-state.isDead:
+                               state.wg.Done()
+                               deadlineTicker.Stop()
+                               pingTicker.Stop()
+                               return
+                       case now := <-deadlineTicker.C:
+                               if now.Sub(state.RxLastNonPing) >= state.onlineDeadline &&
+                                       now.Sub(state.TxLastNonPing) >= state.onlineDeadline {
+                                       goto Deadlined
+                               }
+                               if state.maxOnlineTime > 0 && state.mustFinishAt.Before(now) {
+                                       goto Deadlined
+                               }
+                               if now.Sub(state.RxLastSeen) >= 2*PingTimeout {
+                                       goto Deadlined
+                               }
+                               break
+                       Deadlined:
+                               state.SetDead()
+                               conn.Close()
+                       case now := <-pingTicker.C:
+                               if now.After(state.TxLastSeen.Add(PingTimeout)) {
+                                       state.wg.Add(1)
+                                       go func() {
+                                               state.pings <- struct{}{}
+                                               state.wg.Done()
+                                       }()
+                               }
+                       }
+               }
+       }()
+
+       // Spool checker and INFOs sender of appearing files
        if !state.listOnly && (state.xxOnly == "" || state.xxOnly == TTx) {
+               state.wg.Add(1)
                go func() {
-                       for range time.Tick(time.Second) {
-                               if state.NotAlive() {
+                       dw, err := state.Ctx.NewDirWatcher(
+                               filepath.Join(state.Ctx.Spool, state.Node.Id.String(), string(TTx)),
+                               time.Second,
+                       )
+                       if err != nil {
+                               state.Ctx.LogE("sp-queue-dir-watch", les, err, logMsg)
+                               log.Fatalln(err)
+                       }
+                       for {
+                               select {
+                               case <-state.isDead:
+                                       dw.Close()
+                                       state.wg.Done()
                                        return
-                               }
-                               for _, payload := range state.Ctx.infosOur(
-                                       state.Node.Id,
-                                       state.Nice,
-                                       &state.infosOurSeen,
-                               ) {
-                                       state.Ctx.LogD(
-                                               "sp-work",
-                                               SdsAdd(sds, SDS{"size": len(payload)}),
-                                               "queuing new info",
-                                       )
-                                       state.payloads <- payload
+                               case <-dw.C:
+                                       for _, payload := range state.Ctx.infosOur(
+                                               state.Node.Id,
+                                               state.Nice,
+                                               &state.infosOurSeen,
+                                       ) {
+                                               state.Ctx.LogD(
+                                                       "sp-queue-info",
+                                                       append(les, LE{"Size", int64(len(payload))}),
+                                                       func(les LEs) string {
+                                                               return fmt.Sprintf(
+                                                                       "SP with %s (nice %s): queuing new info (%s)",
+                                                                       state.Node.Name, NicenessFmt(state.Nice),
+                                                                       humanize.IBytes(uint64(len(payload))),
+                                                               )
+                                                       },
+                                               )
+                                               state.payloads <- payload
+                                       }
                                }
                        }
                }()
        }
 
+       // Sender
        state.wg.Add(1)
        go func() {
-               defer func() {
-                       state.isDead = true
-                       state.wg.Done()
-               }()
+               defer conn.Close()
+               defer state.SetDead()
+               defer state.wg.Done()
+               buf := make([]byte, MaxSPSize-SPHeadOverhead-SPFileOverhead)
                for {
                        if state.NotAlive() {
                                return
                        }
                        var payload []byte
+                       var ping bool
                        select {
+                       case <-state.pings:
+                               state.Ctx.LogD("sp-got-ping", les, func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): got ping",
+                                               state.Node.Name, NicenessFmt(state.Nice),
+                                       )
+                               })
+                               payload = SPPingMarshalized
+                               ping = true
                        case payload = <-state.payloads:
                                state.Ctx.LogD(
-                                       "sp-xmit",
-                                       SdsAdd(sds, SDS{"size": len(payload)}),
-                                       "got payload",
+                                       "sp-got-payload",
+                                       append(les, LE{"Size", int64(len(payload))}),
+                                       func(les LEs) string {
+                                               return fmt.Sprintf(
+                                                       "SP with %s (nice %s): got payload (%s)",
+                                                       state.Node.Name, NicenessFmt(state.Nice),
+                                                       humanize.IBytes(uint64(len(payload))),
+                                               )
+                                       },
                                )
                        default:
-                       }
-                       if payload == nil {
                                state.RLock()
                                if len(state.queueTheir) == 0 {
                                        state.RUnlock()
@@ -575,157 +855,250 @@ func (state *SPState) StartWorkers(
                                }
                                freq := state.queueTheir[0].freq
                                state.RUnlock()
-
                                if state.txRate > 0 {
                                        time.Sleep(time.Second / time.Duration(state.txRate))
                                }
-
-                               sdsp := SdsAdd(sds, SDS{
-                                       "xx":   string(TTx),
-                                       "pkt":  ToBase32(freq.Hash[:]),
-                                       "size": int64(freq.Offset),
+                               pktName := Base32Codec.EncodeToString(freq.Hash[:])
+                               lesp := append(
+                                       les,
+                                       LE{"XX", string(TTx)},
+                                       LE{"Pkt", pktName},
+                                       LE{"Size", int64(freq.Offset)},
+                               )
+                               logMsg := func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): tx/%s (%s)",
+                                               state.Node.Name, NicenessFmt(state.Nice),
+                                               pktName,
+                                               humanize.IBytes(freq.Offset),
+                                       )
+                               }
+                               state.Ctx.LogD("sp-queue", lesp, func(les LEs) string {
+                                       return logMsg(les) + ": queueing"
                                })
-                               state.Ctx.LogD("sp-file", sdsp, "queueing")
-                               fd, err := os.Open(filepath.Join(
+                               pth := filepath.Join(
                                        state.Ctx.Spool,
                                        state.Node.Id.String(),
                                        string(TTx),
-                                       ToBase32(freq.Hash[:]),
-                               ))
-                               if err != nil {
-                                       state.Ctx.LogE("sp-file", sdsp, err, "")
-                                       break
-                               }
-                               fi, err := fd.Stat()
-                               if err != nil {
-                                       state.Ctx.LogE("sp-file", sdsp, err, "")
-                                       break
+                                       Base32Codec.EncodeToString(freq.Hash[:]),
+                               )
+                               state.fdsLock.RLock()
+                               fdAndFullSize, exists := state.fds[pth]
+                               state.fdsLock.RUnlock()
+                               if !exists {
+                                       state.Ctx.LogD("sp-queue-open", lesp, func(les LEs) string {
+                                               return logMsg(les) + ": opening"
+                                       })
+                                       fd, err := os.Open(pth)
+                                       if err != nil {
+                                               state.Ctx.LogE("sp-queue-open", lesp, err, func(les LEs) string {
+                                                       return logMsg(les) + ": opening"
+                                               })
+                                               return
+                                       }
+                                       fi, err := fd.Stat()
+                                       if err != nil {
+                                               state.Ctx.LogE("sp-queue-stat", lesp, err, func(les LEs) string {
+                                                       return logMsg(les) + ": stating"
+                                               })
+                                               return
+                                       }
+                                       fdAndFullSize = FdAndFullSize{fd: fd, fullSize: fi.Size()}
+                                       state.fdsLock.Lock()
+                                       state.fds[pth] = fdAndFullSize
+                                       state.fdsLock.Unlock()
                                }
-                               fullSize := fi.Size()
-                               var buf []byte
+                               fd := fdAndFullSize.fd
+                               fullSize := fdAndFullSize.fullSize
+                               lesp = append(lesp, LE{"FullSize", fullSize})
+                               var bufRead []byte
                                if freq.Offset < uint64(fullSize) {
-                                       state.Ctx.LogD("sp-file", sdsp, "seeking")
+                                       state.Ctx.LogD("sp-file-seek", lesp, func(les LEs) string {
+                                               return logMsg(les) + ": seeking"
+                                       })
                                        if _, err = fd.Seek(int64(freq.Offset), io.SeekStart); err != nil {
-                                               state.Ctx.LogE("sp-file", sdsp, err, "")
-                                               break
+                                               state.Ctx.LogE("sp-file-seek", lesp, err, func(les LEs) string {
+                                                       return logMsg(les) + ": seeking"
+                                               })
+                                               return
                                        }
-                                       buf = make([]byte, MaxSPSize-SPHeadOverhead-SPFileOverhead)
                                        n, err := fd.Read(buf)
                                        if err != nil {
-                                               state.Ctx.LogE("sp-file", sdsp, err, "")
-                                               break
+                                               state.Ctx.LogE("sp-file-read", lesp, err, func(les LEs) string {
+                                                       return logMsg(les) + ": reading"
+                                               })
+                                               return
                                        }
-                                       buf = buf[:n]
-                                       state.Ctx.LogD(
-                                               "sp-file",
-                                               SdsAdd(sdsp, SDS{"size": n}),
-                                               "read",
+                                       bufRead = buf[:n]
+                                       lesp = append(
+                                               les,
+                                               LE{"XX", string(TTx)},
+                                               LE{"Pkt", pktName},
+                                               LE{"Size", int64(n)},
+                                               LE{"FullSize", fullSize},
                                        )
+                                       state.Ctx.LogD("sp-file-read", lesp, func(les LEs) string {
+                                               return fmt.Sprintf(
+                                                       "%s: read %s",
+                                                       logMsg(les), humanize.IBytes(uint64(n)),
+                                               )
+                                       })
+                               } else {
+                                       state.closeFd(pth)
                                }
-                               fd.Close()
                                payload = MarshalSP(SPTypeFile, SPFile{
                                        Hash:    freq.Hash,
                                        Offset:  freq.Offset,
-                                       Payload: buf,
+                                       Payload: bufRead,
                                })
-                               ourSize := freq.Offset + uint64(len(buf))
-                               sdsp["size"] = int64(ourSize)
-                               sdsp["fullsize"] = fullSize
+                               ourSize := freq.Offset + uint64(len(bufRead))
+                               lesp = append(
+                                       les,
+                                       LE{"XX", string(TTx)},
+                                       LE{"Pkt", pktName},
+                                       LE{"Size", int64(ourSize)},
+                                       LE{"FullSize", fullSize},
+                               )
                                if state.Ctx.ShowPrgrs {
-                                       Progress("Tx", sdsp)
+                                       state.progressBars[pktName] = struct{}{}
+                                       Progress("Tx", lesp)
+                               }
+                               if ourSize == uint64(fullSize) {
+                                       state.closeFd(pth)
+                                       state.Ctx.LogD("sp-file-finished", lesp, func(les LEs) string {
+                                               return logMsg(les) + ": finished"
+                                       })
+                                       if state.Ctx.ShowPrgrs {
+                                               delete(state.progressBars, pktName)
+                                       }
                                }
                                state.Lock()
-                               if len(state.queueTheir) > 0 && *state.queueTheir[0].freq.Hash == *freq.Hash {
+                               for i, q := range state.queueTheir {
+                                       if *q.freq.Hash != *freq.Hash {
+                                               continue
+                                       }
                                        if ourSize == uint64(fullSize) {
-                                               state.Ctx.LogD("sp-file", sdsp, "finished")
-                                               if len(state.queueTheir) > 1 {
-                                                       state.queueTheir = state.queueTheir[1:]
-                                               } else {
-                                                       state.queueTheir = state.queueTheir[:0]
-                                               }
+                                               state.queueTheir = append(
+                                                       state.queueTheir[:i],
+                                                       state.queueTheir[i+1:]...,
+                                               )
                                        } else {
-                                               state.queueTheir[0].freq.Offset += uint64(len(buf))
+                                               q.freq.Offset = ourSize
                                        }
-                               } else {
-                                       state.Ctx.LogD("sp-file", sdsp, "queue disappeared")
+                                       break
                                }
                                state.Unlock()
                        }
-                       state.Ctx.LogD(
-                               "sp-xmit",
-                               SdsAdd(sds, SDS{"size": len(payload)}),
-                               "sending",
-                       )
-                       conn.SetWriteDeadline(time.Now().Add(DefaultDeadline * time.Second))
-                       if err := state.WriteSP(conn, state.csOur.Encrypt(nil, nil, payload)); err != nil {
-                               state.Ctx.LogE("sp-xmit", sds, err, "")
-                               break
+                       logMsg := func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): sending %s",
+                                       state.Node.Name, NicenessFmt(state.Nice),
+                                       humanize.IBytes(uint64(len(payload))),
+                               )
+                       }
+                       state.Ctx.LogD("sp-sending", append(les, LE{"Size", int64(len(payload))}), logMsg)
+                       conn.SetWriteDeadline(time.Now().Add(DefaultDeadline))
+                       ct, err := state.csOur.Encrypt(nil, nil, payload)
+                       if err != nil {
+                               state.Ctx.LogE("sp-encrypting", les, err, logMsg)
+                               return
+                       }
+                       if err := state.WriteSP(conn, ct, ping); err != nil {
+                               state.Ctx.LogE("sp-sending", les, err, logMsg)
+                               return
                        }
                }
        }()
 
+       // Receiver
        state.wg.Add(1)
        go func() {
-               defer func() {
-                       state.isDead = true
-                       state.wg.Done()
-               }()
                for {
                        if state.NotAlive() {
-                               return
+                               break
                        }
-                       state.Ctx.LogD("sp-recv", sds, "waiting for payload")
-                       conn.SetReadDeadline(time.Now().Add(DefaultDeadline * time.Second))
+                       logMsg := func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): waiting for payload",
+                                       state.Node.Name, NicenessFmt(state.Nice),
+                               )
+                       }
+                       state.Ctx.LogD("sp-recv-wait", les, logMsg)
+                       conn.SetReadDeadline(time.Now().Add(DefaultDeadline))
                        payload, err := state.ReadSP(conn)
                        if err != nil {
                                if err == io.EOF {
                                        break
                                }
                                unmarshalErr := err.(*xdr.UnmarshalError)
-                               netErr, ok := unmarshalErr.Err.(net.Error)
-                               if ok && netErr.Timeout() {
+                               if os.IsTimeout(unmarshalErr.Err) {
                                        continue
                                }
                                if unmarshalErr.ErrorCode == xdr.ErrIO {
                                        break
                                }
-                               state.Ctx.LogE("sp-recv", sds, err, "")
+                               state.Ctx.LogE("sp-recv-wait", les, err, logMsg)
                                break
                        }
+                       logMsg = func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): payload (%s)",
+                                       state.Node.Name, NicenessFmt(state.Nice),
+                                       humanize.IBytes(uint64(len(payload))),
+                               )
+                       }
                        state.Ctx.LogD(
-                               "sp-recv",
-                               SdsAdd(sds, SDS{"size": len(payload)}),
-                               "got payload",
+                               "sp-recv-got",
+                               append(les, LE{"Size", int64(len(payload))}),
+                               func(les LEs) string { return logMsg(les) + ": got" },
                        )
                        payload, err = state.csTheir.Decrypt(nil, nil, payload)
                        if err != nil {
-                               state.Ctx.LogE("sp-recv", sds, err, "")
+                               state.Ctx.LogE("sp-recv-got", les, err, func(les LEs) string {
+                                       return logMsg(les) + ": got"
+                               })
                                break
                        }
                        state.Ctx.LogD(
-                               "sp-recv",
-                               SdsAdd(sds, SDS{"size": len(payload)}),
-                               "processing",
+                               "sp-recv-process",
+                               append(les, LE{"Size", int64(len(payload))}),
+                               func(les LEs) string {
+                                       return logMsg(les) + ": processing"
+                               },
                        )
                        replies, err := state.ProcessSP(payload)
                        if err != nil {
-                               state.Ctx.LogE("sp-recv", sds, err, "")
+                               state.Ctx.LogE("sp-recv-process", les, err, func(les LEs) string {
+                                       return logMsg(les) + ": processing"
+                               })
                                break
                        }
+                       state.wg.Add(1)
                        go func() {
                                for _, reply := range replies {
                                        state.Ctx.LogD(
-                                               "sp-recv",
-                                               SdsAdd(sds, SDS{"size": len(reply)}),
-                                               "queuing reply",
+                                               "sp-recv-reply",
+                                               append(les[:len(les)-1], LE{"Size", int64(len(reply))}),
+                                               func(les LEs) string {
+                                                       return fmt.Sprintf(
+                                                               "SP with %s (nice %s): queuing reply (%s)",
+                                                               state.Node.Name, NicenessFmt(state.Nice),
+                                                               humanize.IBytes(uint64(len(reply))),
+                                                       )
+                                               },
                                        )
                                        state.payloads <- reply
                                }
+                               state.wg.Done()
                        }()
                        if state.rxRate > 0 {
                                time.Sleep(time.Second / time.Duration(state.rxRate))
                        }
                }
+               state.SetDead()
+               state.wg.Done()
+               state.SetDead()
+               conn.Close()
        }()
 
        return nil
@@ -733,8 +1106,10 @@ func (state *SPState) StartWorkers(
 
 func (state *SPState) Wait() {
        state.wg.Wait()
-       state.dirUnlock()
+       close(state.payloads)
+       close(state.pings)
        state.Duration = time.Now().Sub(state.started)
+       state.dirUnlock()
        state.RxSpeed = state.RxBytes
        state.TxSpeed = state.TxBytes
        rxDuration := int64(state.RxLastSeen.Sub(state.started).Seconds())
@@ -745,81 +1120,186 @@ func (state *SPState) Wait() {
        if txDuration > 0 {
                state.TxSpeed = state.TxBytes / txDuration
        }
+       for _, s := range state.fds {
+               s.fd.Close()
+       }
+       for pktName := range state.progressBars {
+               ProgressKill(pktName)
+       }
 }
 
 func (state *SPState) ProcessSP(payload []byte) ([][]byte, error) {
-       sds := SDS{"node": state.Node.Id, "nice": int(state.Nice)}
+       les := LEs{{"Node", state.Node.Id}, {"Nice", int(state.Nice)}}
        r := bytes.NewReader(payload)
        var err error
        var replies [][]byte
        var infosGot bool
        for r.Len() > 0 {
-               state.Ctx.LogD("sp-process", sds, "unmarshaling header")
+               state.Ctx.LogD("sp-process-unmarshal", les, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "SP with %s (nice %s): unmarshaling header",
+                               state.Node.Name, NicenessFmt(state.Nice),
+                       )
+               })
                var head SPHead
                if _, err = xdr.Unmarshal(r, &head); err != nil {
-                       state.Ctx.LogE("sp-process", sds, err, "")
+                       state.Ctx.LogE("sp-process-unmarshal", les, err, func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): unmarshaling header",
+                                       state.Node.Name, NicenessFmt(state.Nice),
+                               )
+                       })
                        return nil, err
                }
+               if head.Type != SPTypePing {
+                       state.RxLastNonPing = state.RxLastSeen
+               }
                switch head.Type {
+               case SPTypeHalt:
+                       state.Ctx.LogD(
+                               "sp-process-halt",
+                               append(les, LE{"Type", "halt"}), func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): got HALT",
+                                               state.Node.Name, NicenessFmt(state.Nice),
+                                       )
+                               },
+                       )
+                       state.Lock()
+                       state.queueTheir = nil
+                       state.Unlock()
+
+               case SPTypePing:
+                       state.Ctx.LogD(
+                               "sp-process-ping",
+                               append(les, LE{"Type", "ping"}),
+                               func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): got PING",
+                                               state.Node.Name, NicenessFmt(state.Nice),
+                                       )
+                               },
+                       )
+
                case SPTypeInfo:
                        infosGot = true
-                       sdsp := SdsAdd(sds, SDS{"type": "info"})
-                       state.Ctx.LogD("sp-process", sdsp, "unmarshaling packet")
+                       lesp := append(les, LE{"Type", "info"})
+                       state.Ctx.LogD(
+                               "sp-process-info-unmarshal", lesp,
+                               func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): unmarshaling INFO",
+                                               state.Node.Name, NicenessFmt(state.Nice),
+                                       )
+                               },
+                       )
                        var info SPInfo
                        if _, err = xdr.Unmarshal(r, &info); err != nil {
-                               state.Ctx.LogE("sp-process", sdsp, err, "")
+                               state.Ctx.LogE(
+                                       "sp-process-info-unmarshal", lesp, err,
+                                       func(les LEs) string {
+                                               return fmt.Sprintf(
+                                                       "SP with %s (nice %s): unmarshaling INFO",
+                                                       state.Node.Name, NicenessFmt(state.Nice),
+                                               )
+                                       },
+                               )
                                return nil, err
                        }
-                       sdsp = SdsAdd(sds, SDS{
-                               "pkt":  ToBase32(info.Hash[:]),
-                               "size": int64(info.Size),
-                               "nice": int(info.Nice),
-                       })
+                       pktName := Base32Codec.EncodeToString(info.Hash[:])
+                       lesp = append(
+                               lesp,
+                               LE{"Pkt", pktName},
+                               LE{"Size", int64(info.Size)},
+                               LE{"PktNice", int(info.Nice)},
+                       )
+                       logMsg := func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): INFO %s (%s) nice %s",
+                                       state.Node.Name, NicenessFmt(state.Nice),
+                                       pktName,
+                                       humanize.IBytes(info.Size),
+                                       NicenessFmt(info.Nice),
+                               )
+                       }
                        if !state.listOnly && info.Nice > state.Nice {
-                               state.Ctx.LogD("sp-process", sdsp, "too nice")
+                               state.Ctx.LogD("sp-process-info-too-nice", lesp, func(les LEs) string {
+                                       return logMsg(les) + ": too nice"
+                               })
                                continue
                        }
-                       state.Ctx.LogD("sp-process", sdsp, "received")
+                       state.Ctx.LogD("sp-process-info-got", lesp, func(les LEs) string {
+                               return logMsg(les) + ": received"
+                       })
                        if !state.listOnly && state.xxOnly == TTx {
                                continue
                        }
                        state.Lock()
                        state.infosTheir[*info.Hash] = &info
                        state.Unlock()
-                       state.Ctx.LogD("sp-process", sdsp, "stating part")
+                       state.Ctx.LogD("sp-process-info-stat", lesp, func(les LEs) string {
+                               return logMsg(les) + ": stating part"
+                       })
                        pktPath := filepath.Join(
                                state.Ctx.Spool,
                                state.Node.Id.String(),
                                string(TRx),
-                               ToBase32(info.Hash[:]),
+                               Base32Codec.EncodeToString(info.Hash[:]),
                        )
+                       logMsg = func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "Packet %s (%s) (nice %s)",
+                                       pktName,
+                                       humanize.IBytes(info.Size),
+                                       NicenessFmt(info.Nice),
+                               )
+                       }
                        if _, err = os.Stat(pktPath); err == nil {
-                               state.Ctx.LogI("sp-info", sdsp, "already done")
+                               state.Ctx.LogI("sp-info-done", lesp, func(les LEs) string {
+                                       return logMsg(les) + ": already done"
+                               })
                                if !state.listOnly {
                                        replies = append(replies, MarshalSP(SPTypeDone, SPDone{info.Hash}))
                                }
                                continue
                        }
-                       if _, err = os.Stat(pktPath + SeenSuffix); err == nil {
-                               state.Ctx.LogI("sp-info", sdsp, "already seen")
+                       if _, err = os.Stat(filepath.Join(
+                               state.Ctx.Spool, state.Node.Id.String(), string(TRx),
+                               SeenDir, Base32Codec.EncodeToString(info.Hash[:]),
+                       )); err == nil {
+                               state.Ctx.LogI("sp-info-seen", lesp, func(les LEs) string {
+                                       return logMsg(les) + ": already seen"
+                               })
                                if !state.listOnly {
                                        replies = append(replies, MarshalSP(SPTypeDone, SPDone{info.Hash}))
                                }
                                continue
                        }
+                       if _, err = os.Stat(pktPath + NoCKSuffix); err == nil {
+                               state.Ctx.LogI("sp-info-nock", lesp, func(les LEs) string {
+                                       return logMsg(les) + ": still not checksummed"
+                               })
+                               continue
+                       }
                        fi, err := os.Stat(pktPath + PartSuffix)
                        var offset int64
                        if err == nil {
                                offset = fi.Size()
                        }
                        if !state.Ctx.IsEnoughSpace(int64(info.Size) - offset) {
-                               state.Ctx.LogI("sp-info", sdsp, "not enough space")
+                               state.Ctx.LogI("sp-info-no-space", lesp, func(les LEs) string {
+                                       return logMsg(les) + ": not enough space"
+                               })
                                continue
                        }
                        state.Ctx.LogI(
                                "sp-info",
-                               SdsAdd(sdsp, SDS{"offset": offset}),
-                               "",
+                               append(lesp, LE{"Offset", offset}),
+                               func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "%s: %d%%", logMsg(les), 100*uint64(offset)/info.Size,
+                                       )
+                               },
                        )
                        if !state.listOnly && (state.onlyPkts == nil || state.onlyPkts[*info.Hash]) {
                                replies = append(replies, MarshalSP(
@@ -827,131 +1307,318 @@ func (state *SPState) ProcessSP(payload []byte) ([][]byte, error) {
                                        SPFreq{info.Hash, uint64(offset)},
                                ))
                        }
+
                case SPTypeFile:
-                       sdsp := SdsAdd(sds, SDS{"type": "file"})
-                       state.Ctx.LogD("sp-process", sdsp, "unmarshaling packet")
+                       lesp := append(les, LE{"Type", "file"})
+                       state.Ctx.LogD("sp-process-file", lesp, func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): unmarshaling FILE",
+                                       state.Node.Name, NicenessFmt(state.Nice),
+                               )
+                       })
                        var file SPFile
                        if _, err = xdr.Unmarshal(r, &file); err != nil {
-                               state.Ctx.LogE("sp-process", SdsAdd(sds, SDS{"type": "file"}), err, "")
+                               state.Ctx.LogE("sp-process-file", lesp, err, func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): unmarshaling FILE",
+                                               state.Node.Name, NicenessFmt(state.Nice),
+                                       )
+                               })
                                return nil, err
                        }
-                       sdsp["xx"] = string(TRx)
-                       sdsp["pkt"] = ToBase32(file.Hash[:])
-                       sdsp["size"] = len(file.Payload)
+                       pktName := Base32Codec.EncodeToString(file.Hash[:])
+                       lesp = append(
+                               lesp,
+                               LE{"XX", string(TRx)},
+                               LE{"Pkt", pktName},
+                               LE{"Size", int64(len(file.Payload))},
+                       )
+                       logMsg := func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "Got packet %s (%s)",
+                                       pktName, humanize.IBytes(uint64(len(file.Payload))),
+                               )
+                       }
+                       fullsize := int64(0)
+                       state.RLock()
+                       infoTheir := state.infosTheir[*file.Hash]
+                       state.RUnlock()
+                       if infoTheir == nil {
+                               state.Ctx.LogE("sp-file-open", lesp, err, func(les LEs) string {
+                                       return logMsg(les) + ": unknown file"
+                               })
+                               continue
+                       }
+                       fullsize = int64(infoTheir.Size)
+                       lesp = append(lesp, LE{"FullSize", fullsize})
                        dirToSync := filepath.Join(
                                state.Ctx.Spool,
                                state.Node.Id.String(),
                                string(TRx),
                        )
-                       filePath := filepath.Join(dirToSync, ToBase32(file.Hash[:]))
-                       state.Ctx.LogD("sp-file", sdsp, "opening part")
-                       fd, err := os.OpenFile(
-                               filePath+PartSuffix,
-                               os.O_RDWR|os.O_CREATE,
-                               os.FileMode(0666),
-                       )
-                       if err != nil {
-                               state.Ctx.LogE("sp-file", sdsp, err, "")
-                               return nil, err
+                       filePath := filepath.Join(dirToSync, pktName)
+                       filePathPart := filePath + PartSuffix
+                       state.Ctx.LogD("sp-file-open", lesp, func(les LEs) string {
+                               return logMsg(les) + ": opening part"
+                       })
+                       state.fdsLock.RLock()
+                       fdAndFullSize, exists := state.fds[filePathPart]
+                       state.fdsLock.RUnlock()
+                       hasherAndOffset := state.fileHashers[filePath]
+                       var fd *os.File
+                       if exists {
+                               fd = fdAndFullSize.fd
+                       } else {
+                               fd, err = os.OpenFile(
+                                       filePathPart,
+                                       os.O_RDWR|os.O_CREATE,
+                                       os.FileMode(0666),
+                               )
+                               if err != nil {
+                                       state.Ctx.LogE("sp-file-open", lesp, err, func(les LEs) string {
+                                               return logMsg(les) + ": opening part"
+                                       })
+                                       return nil, err
+                               }
+                               state.fdsLock.Lock()
+                               state.fds[filePathPart] = FdAndFullSize{fd: fd}
+                               state.fdsLock.Unlock()
+                               if !state.NoCK {
+                                       hasherAndOffset = &MTHAndOffset{
+                                               mth:    MTHNew(fullsize, int64(file.Offset)),
+                                               offset: file.Offset,
+                                       }
+                                       state.fileHashers[filePath] = hasherAndOffset
+                               }
                        }
                        state.Ctx.LogD(
-                               "sp-file",
-                               SdsAdd(sdsp, SDS{"offset": file.Offset}),
-                               "seeking",
-                       )
+                               "sp-file-seek",
+                               append(lesp, LE{"Offset", file.Offset}),
+                               func(les LEs) string {
+                                       return fmt.Sprintf("%s: seeking %d", logMsg(les), file.Offset)
+                               })
                        if _, err = fd.Seek(int64(file.Offset), io.SeekStart); err != nil {
-                               state.Ctx.LogE("sp-file", sdsp, err, "")
-                               fd.Close()
+                               state.Ctx.LogE("sp-file-seek", lesp, err, func(les LEs) string {
+                                       return logMsg(les) + ": seeking"
+                               })
+                               state.closeFd(filePathPart)
                                return nil, err
                        }
-                       state.Ctx.LogD("sp-file", sdsp, "writing")
-                       _, err = fd.Write(file.Payload)
-                       if err != nil {
-                               state.Ctx.LogE("sp-file", sdsp, err, "")
-                               fd.Close()
+                       state.Ctx.LogD("sp-file-write", lesp, func(les LEs) string {
+                               return logMsg(les) + ": writing"
+                       })
+                       if _, err = fd.Write(file.Payload); err != nil {
+                               state.Ctx.LogE("sp-file-write", lesp, err, func(les LEs) string {
+                                       return logMsg(les) + ": writing"
+                               })
+                               state.closeFd(filePathPart)
                                return nil, err
                        }
-                       ourSize := file.Offset + uint64(len(file.Payload))
-                       state.RLock()
-                       sdsp["size"] = int64(ourSize)
-                       sdsp["fullsize"] = int64(state.infosTheir[*file.Hash].Size)
+                       if hasherAndOffset != nil {
+                               if hasherAndOffset.offset == file.Offset {
+                                       if _, err = hasherAndOffset.mth.Write(file.Payload); err != nil {
+                                               panic(err)
+                                       }
+                                       hasherAndOffset.offset += uint64(len(file.Payload))
+                               } else {
+                                       state.Ctx.LogE(
+                                               "sp-file-offset-differs", lesp, errors.New("offset differs"),
+                                               func(les LEs) string {
+                                                       return logMsg(les) + ": deleting hasher"
+                                               },
+                                       )
+                                       delete(state.fileHashers, filePath)
+                                       hasherAndOffset = nil
+                               }
+                       }
+                       ourSize := int64(file.Offset + uint64(len(file.Payload)))
+                       lesp[len(lesp)-2].V = ourSize
                        if state.Ctx.ShowPrgrs {
-                               Progress("Rx", sdsp)
+                               state.progressBars[pktName] = struct{}{}
+                               Progress("Rx", lesp)
                        }
-                       if state.infosTheir[*file.Hash].Size != ourSize {
-                               state.RUnlock()
-                               fd.Close()
+                       if fullsize != ourSize {
                                continue
                        }
-                       state.RUnlock()
-                       spWorkersGroup.Wait()
-                       spWorkersGroup.Add(1)
-                       go func() {
-                               if err := fd.Sync(); err != nil {
-                                       state.Ctx.LogE("sp-file", sdsp, err, "sync")
-                                       fd.Close()
-                                       return
-                               }
-                               state.wg.Add(1)
-                               defer state.wg.Done()
-                               fd.Seek(0, io.SeekStart)
-                               state.Ctx.LogD("sp-file", sdsp, "checking")
-                               gut, err := Check(fd, file.Hash[:], sdsp, state.Ctx.ShowPrgrs)
-                               fd.Close()
-                               if err != nil || !gut {
-                                       state.Ctx.LogE("sp-file", sdsp, errors.New("checksum mismatch"), "")
-                                       return
+                       if state.Ctx.ShowPrgrs {
+                               delete(state.progressBars, pktName)
+                       }
+                       logMsg = func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "Got packet %s %d%% (%s / %s)",
+                                       pktName, 100*ourSize/fullsize,
+                                       humanize.IBytes(uint64(ourSize)),
+                                       humanize.IBytes(uint64(fullsize)),
+                               )
+                       }
+                       err = fd.Sync()
+                       if err != nil {
+                               state.Ctx.LogE("sp-file-sync", lesp, err, func(les LEs) string {
+                                       return logMsg(les) + ": syncing"
+                               })
+                               state.closeFd(filePathPart)
+                               continue
+                       }
+                       if hasherAndOffset != nil {
+                               delete(state.fileHashers, filePath)
+                               if hasherAndOffset.mth.PreaddSize() == 0 {
+                                       if bytes.Compare(hasherAndOffset.mth.Sum(nil), file.Hash[:]) != 0 {
+                                               state.Ctx.LogE(
+                                                       "sp-file-bad-checksum", lesp,
+                                                       errors.New("checksum mismatch"),
+                                                       logMsg,
+                                               )
+                                               state.closeFd(filePathPart)
+                                               continue
+                                       }
+                                       if err = os.Rename(filePathPart, filePath); err != nil {
+                                               state.Ctx.LogE("sp-file-rename", lesp, err, func(les LEs) string {
+                                                       return logMsg(les) + ": renaming"
+                                               })
+                                               state.closeFd(filePathPart)
+                                               continue
+                                       }
+                                       if err = DirSync(dirToSync); err != nil {
+                                               state.Ctx.LogE("sp-file-dirsync", lesp, err, func(les LEs) string {
+                                                       return logMsg(les) + ": dirsyncing"
+                                               })
+                                               state.closeFd(filePathPart)
+                                               continue
+                                       }
+                                       state.Ctx.LogI("sp-file-done", lesp, func(les LEs) string {
+                                               return logMsg(les) + ": done"
+                                       })
+                                       state.wg.Add(1)
+                                       go func() {
+                                               state.payloads <- MarshalSP(SPTypeDone, SPDone{file.Hash})
+                                               state.wg.Done()
+                                       }()
+                                       state.Lock()
+                                       delete(state.infosTheir, *file.Hash)
+                                       state.Unlock()
+                                       if !state.Ctx.HdrUsage {
+                                               continue
+                                       }
+                                       if _, err = fd.Seek(0, io.SeekStart); err != nil {
+                                               state.Ctx.LogE("sp-file-seek", lesp, err, func(les LEs) string {
+                                                       return logMsg(les) + ": seeking"
+                                               })
+                                               state.closeFd(filePathPart)
+                                               continue
+                                       }
+                                       _, pktEncRaw, err := state.Ctx.HdrRead(fd)
+                                       state.closeFd(filePathPart)
+                                       if err != nil {
+                                               state.Ctx.LogE("sp-file-hdr-read", lesp, err, func(les LEs) string {
+                                                       return logMsg(les) + ": HdrReading"
+                                               })
+                                               continue
+                                       }
+                                       state.Ctx.HdrWrite(pktEncRaw, filePath)
+                                       continue
                                }
-                               state.Ctx.LogI("sp-done", SdsAdd(sdsp, SDS{"xx": string(TRx)}), "")
-                               if err = os.Rename(filePath+PartSuffix, filePath); err != nil {
-                                       state.Ctx.LogE("sp-file", sdsp, err, "rename")
-                                       return
+                       }
+                       state.closeFd(filePathPart)
+                       if err = os.Rename(filePathPart, filePath+NoCKSuffix); err != nil {
+                               state.Ctx.LogE("sp-file-rename", lesp, err, func(les LEs) string {
+                                       return logMsg(les) + ": renaming"
+                               })
+                               continue
+                       }
+                       if err = DirSync(dirToSync); err != nil {
+                               state.Ctx.LogE("sp-file-dirsync", lesp, err, func(les LEs) string {
+                                       return logMsg(les) + ": dirsyncing"
+                               })
+                               continue
+                       }
+                       state.Ctx.LogI("sp-file-downloaded", lesp, func(les LEs) string {
+                               return logMsg(les) + ": downloaded"
+                       })
+                       state.Lock()
+                       delete(state.infosTheir, *file.Hash)
+                       state.Unlock()
+                       go func() {
+                               t := SPCheckerTask{
+                                       nodeId: state.Node.Id,
+                                       hsh:    file.Hash,
+                                       done:   state.payloads,
                                }
-                               if err = DirSync(dirToSync); err != nil {
-                                       state.Ctx.LogE("sp-file", sdsp, err, "sync")
-                                       return
+                               if hasherAndOffset != nil {
+                                       t.mth = hasherAndOffset.mth
                                }
-                               state.Lock()
-                               delete(state.infosTheir, *file.Hash)
-                               state.Unlock()
-                               spWorkersGroup.Done()
-                               go func() {
-                                       state.payloads <- MarshalSP(SPTypeDone, SPDone{file.Hash})
-                               }()
+                               spCheckerTasks <- t
                        }()
+
                case SPTypeDone:
-                       sdsp := SdsAdd(sds, SDS{"type": "done"})
-                       state.Ctx.LogD("sp-process", sdsp, "unmarshaling packet")
+                       lesp := append(les, LE{"Type", "done"})
+                       state.Ctx.LogD("sp-process-done-unmarshal", lesp, func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): unmarshaling DONE",
+                                       state.Node.Name, NicenessFmt(state.Nice),
+                               )
+                       })
                        var done SPDone
                        if _, err = xdr.Unmarshal(r, &done); err != nil {
-                               state.Ctx.LogE("sp-process", SdsAdd(sds, SDS{"type": "done"}), err, "")
+                               state.Ctx.LogE("sp-process-done-unmarshal", lesp, err, func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): unmarshaling DONE",
+                                               state.Node.Name, NicenessFmt(state.Nice),
+                                       )
+                               })
                                return nil, err
                        }
-                       sdsp["pkt"] = ToBase32(done.Hash[:])
-                       state.Ctx.LogD("sp-done", sdsp, "removing")
-                       err := os.Remove(filepath.Join(
+                       pktName := Base32Codec.EncodeToString(done.Hash[:])
+                       lesp = append(lesp, LE{"Pkt", pktName}, LE{"XX", string(TTx)})
+                       logMsg := func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): DONE: removing %s",
+                                       state.Node.Name, NicenessFmt(state.Nice), pktName,
+                               )
+                       }
+                       state.Ctx.LogD("sp-done", lesp, logMsg)
+                       pth := filepath.Join(
                                state.Ctx.Spool,
                                state.Node.Id.String(),
                                string(TTx),
-                               ToBase32(done.Hash[:]),
-                       ))
-                       sdsp["xx"] = string(TTx)
-                       if err == nil {
-                               state.Ctx.LogI("sp-done", sdsp, "")
+                               pktName,
+                       )
+                       if err = os.Remove(pth); err == nil {
+                               state.Ctx.LogI("sp-done", lesp, func(les LEs) string {
+                                       return fmt.Sprintf("Packet %s is sent", pktName)
+                               })
+                               if state.Ctx.HdrUsage {
+                                       os.Remove(JobPath2Hdr(pth))
+                               }
                        } else {
-                               state.Ctx.LogE("sp-done", sdsp, err, "")
+                               state.Ctx.LogE("sp-done", lesp, err, logMsg)
                        }
+
                case SPTypeFreq:
-                       sdsp := SdsAdd(sds, SDS{"type": "freq"})
-                       state.Ctx.LogD("sp-process", sdsp, "unmarshaling packet")
+                       lesp := append(les, LE{"Type", "freq"})
+                       state.Ctx.LogD("sp-process-freq", lesp, func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): unmarshaling FREQ",
+                                       state.Node.Name, NicenessFmt(state.Nice),
+                               )
+                       })
                        var freq SPFreq
                        if _, err = xdr.Unmarshal(r, &freq); err != nil {
-                               state.Ctx.LogE("sp-process", sdsp, err, "")
+                               state.Ctx.LogE("sp-process-freq", lesp, err, func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): unmarshaling FREQ",
+                                               state.Node.Name, NicenessFmt(state.Nice),
+                                       )
+                               })
                                return nil, err
                        }
-                       sdsp["pkt"] = ToBase32(freq.Hash[:])
-                       sdsp["offset"] = freq.Offset
-                       state.Ctx.LogD("sp-process", sdsp, "queueing")
+                       pktName := Base32Codec.EncodeToString(freq.Hash[:])
+                       lesp = append(lesp, LE{"Pkt", pktName}, LE{"Offset", freq.Offset})
+                       state.Ctx.LogD("sp-process-freq-queueing", lesp, func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "SP with %s (nice %s): FREQ %s: queuing",
+                                       state.Node.Name, NicenessFmt(state.Nice), pktName,
+                               )
+                       })
                        nice, exists := state.infosOurSeen[*freq.Hash]
                        if exists {
                                if state.onlyPkts == nil || !state.onlyPkts[*freq.Hash] {
@@ -968,26 +1635,38 @@ func (state *SPState) ProcessSP(payload []byte) ([][]byte, error) {
                                        state.queueTheir[insertIdx] = &FreqWithNice{&freq, nice}
                                        state.Unlock()
                                } else {
-                                       state.Ctx.LogD("sp-process", sdsp, "skipping")
+                                       state.Ctx.LogD("sp-process-freq-skip", lesp, func(les LEs) string {
+                                               return fmt.Sprintf(
+                                                       "SP with %s (nice %s): FREQ %s: skipping",
+                                                       state.Node.Name, NicenessFmt(state.Nice), pktName,
+                                               )
+                                       })
                                }
                        } else {
-                               state.Ctx.LogD("sp-process", sdsp, "unknown")
+                               state.Ctx.LogD("sp-process-freq-unknown", lesp, func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): FREQ %s: unknown",
+                                               state.Node.Name, NicenessFmt(state.Nice), pktName,
+                                       )
+                               })
                        }
-               case SPTypeHalt:
-                       state.Ctx.LogD("sp-process", SdsAdd(sds, SDS{"type": "halt"}), "")
-                       state.Lock()
-                       state.queueTheir = nil
-                       state.Unlock()
+
                default:
                        state.Ctx.LogE(
-                               "sp-process",
-                               SdsAdd(sds, SDS{"type": head.Type}),
+                               "sp-process-type-unknown",
+                               append(les, LE{"Type", head.Type}),
                                errors.New("unknown type"),
-                               "",
+                               func(les LEs) string {
+                                       return fmt.Sprintf(
+                                               "SP with %s (nice %s): %d",
+                                               state.Node.Name, NicenessFmt(state.Nice), head.Type,
+                                       )
+                               },
                        )
                        return nil, BadPktType
                }
        }
+
        if infosGot {
                var pkts int
                var size uint64
@@ -997,12 +1676,55 @@ func (state *SPState) ProcessSP(payload []byte) ([][]byte, error) {
                        size += info.Size
                }
                state.RUnlock()
-               state.Ctx.LogI("sp-infos", SDS{
-                       "xx":   string(TRx),
-                       "node": state.Node.Id,
-                       "pkts": pkts,
-                       "size": int64(size),
-               }, "")
+               state.Ctx.LogI("sp-infos-rx", LEs{
+                       {"XX", string(TRx)},
+                       {"Node", state.Node.Id},
+                       {"Pkts", pkts},
+                       {"Size", int64(size)},
+               }, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "%s has got for us: %d packets, %s",
+                               state.Node.Name, pkts, humanize.IBytes(size),
+                       )
+               })
        }
        return payloadsSplit(replies), nil
 }
+
+func SPChecker(ctx *Ctx) {
+       for t := range spCheckerTasks {
+               pktName := Base32Codec.EncodeToString(t.hsh[:])
+               les := LEs{
+                       {"XX", string(TRx)},
+                       {"Node", t.nodeId},
+                       {"Pkt", pktName},
+               }
+               SPCheckerWg.Add(1)
+               ctx.LogD("sp-checker", les, func(les LEs) string {
+                       return fmt.Sprintf("Checksumming %s/rx/%s", ctx.NodeName(t.nodeId), pktName)
+               })
+               size, err := ctx.CheckNoCK(t.nodeId, t.hsh, t.mth)
+               les = append(les, LE{"Size", size})
+               if err != nil {
+                       ctx.LogE("sp-checker", les, err, func(les LEs) string {
+                               return fmt.Sprintf(
+                                       "Checksumming %s/rx/%s (%s)", ctx.NodeName(t.nodeId), pktName,
+                                       humanize.IBytes(uint64(size)),
+                               )
+                       })
+                       SPCheckerWg.Done()
+                       continue
+               }
+               ctx.LogI("sp-checker-done", les, func(les LEs) string {
+                       return fmt.Sprintf(
+                               "Packet %s is retreived (%s)",
+                               pktName, humanize.IBytes(uint64(size)),
+                       )
+               })
+               SPCheckerWg.Done()
+               go func(t SPCheckerTask) {
+                       defer func() { recover() }()
+                       t.done <- MarshalSP(SPTypeDone, SPDone{t.hsh})
+               }(t)
+       }
+}