test/gc2.go

   1 // $G $D/$F.go && $L $F.$A && ./$A.out
   2
   3 // Copyright 2011 The Go Authors.  All rights reserved.
   4 // Use of this source code is governed by a BSD-style
   5 // license that can be found in the LICENSE file.
   6
   7 // Check that buffered channels are garbage collected properly.
   8 // An interesting case because they have finalizers and used to
   9 // have self loops that kept them from being collected.
  10 // (Cyclic data with finalizers is never finalized, nor collected.)
  11
  12 package main
  13
  14 import (
  15         "fmt"
  16         "os"
  17         "runtime"
  18 )
  19
  20 func main() {
  21         const N = 10000
  22         st := runtime.MemStats
  23         for i := 0; i < N; i++ {
  24                 c := make(chan int, 10)
  25                 _ = c
  26                 if i%100 == 0 {
  27                         for j := 0; j < 4; j++ {
  28                                 runtime.GC()
  29                                 runtime.Gosched()
  30                                 runtime.GC()
  31                                 runtime.Gosched()
  32                         }
  33                 }
  34         }
  35
  36         obj := runtime.MemStats.HeapObjects - st.HeapObjects
  37         if obj > N/5 {
  38                 fmt.Println("too many objects left:", obj)
  39                 os.Exit(1)
  40         }
  41 }