mirror of
https://github.com/golang/go
synced 2024-11-13 17:20:22 -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
|
|
|
|
// Copyright 2011 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
// Check that buffered channels are garbage collected properly.
|
|
// An interesting case because they have finalizers and used to
|
|
// have self loops that kept them from being collected.
|
|
// (Cyclic data with finalizers is never finalized, nor collected.)
|
|
|
|
package main
|
|
|
|
import (
|
|
"fmt"
|
|
"os"
|
|
"runtime"
|
|
)
|
|
|
|
func main() {
|
|
const N = 10000
|
|
st := runtime.MemStats
|
|
for i := 0; i < N; i++ {
|
|
c := make(chan int, 10)
|
|
_ = c
|
|
if i%100 == 0 {
|
|
for j := 0; j < 4; j++ {
|
|
runtime.GC()
|
|
runtime.Gosched()
|
|
runtime.GC()
|
|
runtime.Gosched()
|
|
}
|
|
}
|
|
}
|
|
|
|
obj := runtime.MemStats.HeapObjects - st.HeapObjects
|
|
if obj > N/5 {
|
|
fmt.Println("too many objects left:", obj)
|
|
os.Exit(1)
|
|
}
|
|
}
|