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go/usr/rsc/mem/testrandom.go
Russ Cox 3f8aa662e9 add support for ref counts to memory allocator.
mark and sweep, stop the world garbage collector
(intermediate step in the way to ref counting).
can run pretty with an explicit gc after each file.

R=r
DELTA=502  (346 added, 143 deleted, 13 changed)
OCL=20630
CL=20635
2008-12-05 15:24:18 -08:00

69 lines
1.6 KiB
Go

// 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.
package main
import (
"allocator";
"rand";
"syscall"
)
var footprint int64;
var allocated int64;
func bigger() {
if footprint < allocator.footprint {
footprint = allocator.footprint;
println("Footprint", footprint, " for ", allocated);
if footprint > 1e9 {
panicln("too big");
}
}
}
// 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 := allocator.malloc(1<<uint(i));
allocator.free(b);
}
for i := 0; i < 256; i++ {
b := allocator.malloc(i<<12);
allocator.free(b);
}
}
func main() {
// prime();
var blocks [1] struct { base *byte; siz int; };
for i := 0; i < 1 << 20; i++ {
if i%(1<<10) == 0 {
println(i);
}
b := rand.rand() % len(blocks);
if blocks[b].base != nil {
// println("Free", blocks[b].siz, blocks[b].base);
allocator.free(blocks[b].base);
blocks[b].base = nil;
allocated -= int64(blocks[b].siz);
continue
}
siz := rand.rand() >> (11 + rand.urand32() % 20);
base := allocator.malloc(siz);
ptr := uint64(syscall.BytePtr(base))+uint64(siz/2);
obj, size, ref, ok := allocator.find(ptr);
if obj != base || *ref != 0 || !ok {
panicln("find", siz, obj, ref, ok);
}
blocks[b].base = base;
blocks[b].siz = siz;
allocated += int64(siz);
// println("Alloc", siz, base);
allocator.memset(base, 0xbb, siz);
bigger();
}
}