mirror of
https://github.com/golang/go
synced 2024-11-19 15:44:44 -07:00
507df959e4
The list elements are already being allocated out of a single memory buffer. We can drop the Link* pointer following and the memory it requires, replacing it with index operations. The change also keeps a channel from containing a pointer back into its own allocation block, which would create a cycle. Blocks involved in cycles are not guaranteed to be finalized properly, and channels depend on finalizers to free OS-level locks on some systems. The self-reference was keeping channels from being garbage collected. runtime-gdb.py will need to be updated in order to dump the content of buffered channels with the new data structure. Fixes #1676. R=ken2, r CC=golang-dev https://golang.org/cl/4411045
42 lines
890 B
Go
42 lines
890 B
Go
// $G $D/$F.go && $L $F.$A && ./$A.out
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// Copyright 2011 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Check that buffered channels are garbage collected properly.
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// An interesting case because they have finalizers and used to
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// have self loops that kept them from being collected.
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// (Cyclic data with finalizers is never finalized, nor collected.)
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package main
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import (
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"fmt"
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"os"
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"runtime"
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)
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func main() {
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const N = 10000
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st := runtime.MemStats
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for i := 0; i < N; i++ {
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c := make(chan int, 10)
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_ = c
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if i%100 == 0 {
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for j := 0; j < 4; j++ {
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runtime.GC()
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runtime.Gosched()
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runtime.GC()
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runtime.Gosched()
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}
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}
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}
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obj := runtime.MemStats.HeapObjects - st.HeapObjects
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if obj > N/5 {
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fmt.Println("too many objects left:", obj)
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os.Exit(1)
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}
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}
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