diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:23:18 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-16 19:23:18 +0000 |
commit | 43a123c1ae6613b3efeed291fa552ecd909d3acf (patch) | |
tree | fd92518b7024bc74031f78a1cf9e454b65e73665 /test/finprofiled.go | |
parent | Initial commit. (diff) | |
download | golang-1.20-43a123c1ae6613b3efeed291fa552ecd909d3acf.tar.xz golang-1.20-43a123c1ae6613b3efeed291fa552ecd909d3acf.zip |
Adding upstream version 1.20.14.upstream/1.20.14upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | test/finprofiled.go | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/test/finprofiled.go b/test/finprofiled.go new file mode 100644 index 0000000..ca7e3c8 --- /dev/null +++ b/test/finprofiled.go @@ -0,0 +1,74 @@ +// run + +// Copyright 2015 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. + +// Test that tiny allocations with finalizers are correctly profiled. +// Previously profile special records could have been processed prematurely +// (while the object is still live). + +package main + +import ( + "runtime" + "time" + "unsafe" +) + +func main() { + runtime.MemProfileRate = 1 + // Allocate 1M 4-byte objects and set a finalizer for every third object. + // Assuming that tiny block size is 16, some objects get finalizers setup + // only for middle bytes. The finalizer resurrects that object. + // As the result, all allocated memory must stay alive. + const ( + N = 1 << 20 + tinyBlockSize = 16 // runtime._TinySize + ) + hold := make([]*int32, 0, N) + for i := 0; i < N; i++ { + x := new(int32) + if i%3 == 0 { + runtime.SetFinalizer(x, func(p *int32) { + hold = append(hold, p) + }) + } + } + // Finalize as much as possible. + // Note: the sleep only increases probability of bug detection, + // it cannot lead to false failure. + for i := 0; i < 5; i++ { + runtime.GC() + time.Sleep(10 * time.Millisecond) + } + // Read memory profile. + var prof []runtime.MemProfileRecord + for { + if n, ok := runtime.MemProfile(prof, false); ok { + prof = prof[:n] + break + } else { + prof = make([]runtime.MemProfileRecord, n+10) + } + } + // See how much memory in tiny objects is profiled. + var totalBytes int64 + for _, p := range prof { + bytes := p.AllocBytes - p.FreeBytes + nobj := p.AllocObjects - p.FreeObjects + size := bytes / nobj + if size == tinyBlockSize { + totalBytes += bytes + } + } + // 2*tinyBlockSize slack is for any boundary effects. + if want := N*int64(unsafe.Sizeof(int32(0))) - 2*tinyBlockSize; totalBytes < want { + println("got", totalBytes, "want >=", want) + panic("some of the tiny objects are not profiled") + } + // Just to keep hold alive. + if len(hold) != 0 && hold[0] == nil { + panic("bad") + } +} |