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99a1c74a6a
It was 50% of our allocs on one of our servers. (!!) Updates #2784 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
51 lines
963 B
Go
51 lines
963 B
Go
// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package metrics
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import (
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"os"
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"runtime"
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"testing"
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)
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func TestCurrentFileDescriptors(t *testing.T) {
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if runtime.GOOS != "linux" {
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t.Skipf("skipping on %v", runtime.GOOS)
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}
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n := CurrentFDs()
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if n < 3 {
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t.Fatalf("got %v; want >= 3", n)
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}
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allocs := int(testing.AllocsPerRun(100, func() {
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n = CurrentFDs()
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}))
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if allocs != 0 {
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t.Errorf("allocs = %v; want 0", allocs)
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}
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// Open some FDs.
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const extra = 10
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for i := 0; i < extra; i++ {
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f, err := os.Open("/proc/self/stat")
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if err != nil {
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t.Fatal(err)
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}
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defer f.Close()
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}
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n2 := CurrentFDs()
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if n2 != n+extra {
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t.Errorf("fds changed from %v => %v, want to %v", n, n2, n+extra)
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}
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}
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func BenchmarkCurrentFileDescriptors(b *testing.B) {
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b.ReportAllocs()
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for i := 0; i < b.N; i++ {
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_ = CurrentFDs()
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}
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}
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