mirror of
https://github.com/golang/go
synced 2024-11-24 11:40:16 -07:00
4f61fc96b2
The ken directory is untouched so we have some examples with explicit semis. R=gri CC=golang-dev https://golang.org/cl/2157041
92 lines
1.9 KiB
Go
92 lines
1.9 KiB
Go
// $G $D/$F.go && $L $F.$A && ./$A.out
|
|
|
|
// Copyright 2009 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.
|
|
|
|
// Random malloc test.
|
|
|
|
package main
|
|
|
|
import (
|
|
"flag"
|
|
"rand"
|
|
"runtime"
|
|
"unsafe"
|
|
)
|
|
|
|
var chatty = flag.Bool("v", false, "chatty")
|
|
|
|
var footprint uint64
|
|
var allocated uint64
|
|
|
|
func bigger() {
|
|
if f := runtime.MemStats.Sys; footprint < f {
|
|
footprint = f
|
|
if *chatty {
|
|
println("Footprint", footprint, " for ", allocated)
|
|
}
|
|
if footprint > 1e9 {
|
|
println("too big")
|
|
panic("fail")
|
|
}
|
|
}
|
|
}
|
|
|
|
// Prime the data structures by allocating one of
|
|
// each block in order. After this, there should be
|
|
// little reason to ask for more memory from the OS.
|
|
func prime() {
|
|
for i := 0; i < 16; i++ {
|
|
b := runtime.Alloc(1 << uint(i))
|
|
runtime.Free(b)
|
|
}
|
|
for i := uintptr(0); i < 256; i++ {
|
|
b := runtime.Alloc(i << 12)
|
|
runtime.Free(b)
|
|
}
|
|
}
|
|
|
|
func memset(b *byte, c byte, n uintptr) {
|
|
np := uintptr(n)
|
|
for i := uintptr(0); i < np; i++ {
|
|
*(*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(b)) + i)) = c
|
|
}
|
|
}
|
|
|
|
func main() {
|
|
flag.Parse()
|
|
// prime()
|
|
var blocks [1]struct {
|
|
base *byte
|
|
siz uintptr
|
|
}
|
|
for i := 0; i < 1<<10; i++ {
|
|
if i%(1<<10) == 0 && *chatty {
|
|
println(i)
|
|
}
|
|
b := rand.Int() % len(blocks)
|
|
if blocks[b].base != nil {
|
|
// println("Free", blocks[b].siz, blocks[b].base)
|
|
runtime.Free(blocks[b].base)
|
|
blocks[b].base = nil
|
|
allocated -= uint64(blocks[b].siz)
|
|
continue
|
|
}
|
|
siz := uintptr(rand.Int() >> (11 + rand.Uint32()%20))
|
|
base := runtime.Alloc(siz)
|
|
// ptr := uintptr(syscall.BytePtr(base))+uintptr(siz/2)
|
|
// obj, size, ref, ok := allocator.find(ptr)
|
|
// if obj != base || *ref != 0 || !ok {
|
|
// println("find", siz, obj, ref, ok)
|
|
// panic("fail")
|
|
// }
|
|
blocks[b].base = base
|
|
blocks[b].siz = siz
|
|
allocated += uint64(siz)
|
|
// println("Alloc", siz, base)
|
|
memset(base, 0xbb, siz)
|
|
bigger()
|
|
}
|
|
}
|