From 47ab3d4a42e9ab51c465c4322d2ec233f6324e6b Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 15:16:40 +0200 Subject: Adding upstream version 1.18.10. Signed-off-by: Daniel Baumann --- test/chan/select2.go | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 test/chan/select2.go (limited to 'test/chan/select2.go') diff --git a/test/chan/select2.go b/test/chan/select2.go new file mode 100644 index 0000000..31e27d7 --- /dev/null +++ b/test/chan/select2.go @@ -0,0 +1,54 @@ +// run + +// Copyright 2010 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 selects do not consume undue memory. + +package main + +import "runtime" + +func sender(c chan int, n int) { + for i := 0; i < n; i++ { + c <- 1 + } +} + +func receiver(c, dummy chan int, n int) { + for i := 0; i < n; i++ { + select { + case <-c: + // nothing + case <-dummy: + panic("dummy") + } + } +} + +func main() { + runtime.MemProfileRate = 0 + + c := make(chan int) + dummy := make(chan int) + + // warm up + go sender(c, 100000) + receiver(c, dummy, 100000) + runtime.GC() + memstats := new(runtime.MemStats) + runtime.ReadMemStats(memstats) + alloc := memstats.Alloc + + // second time shouldn't increase footprint by much + go sender(c, 100000) + receiver(c, dummy, 100000) + runtime.GC() + runtime.ReadMemStats(memstats) + + // Be careful to avoid wraparound. + if memstats.Alloc > alloc && memstats.Alloc-alloc > 1.1e5 { + println("BUG: too much memory for 100,000 selects:", memstats.Alloc-alloc) + } +} -- cgit v1.2.3