tailscale/metrics/metrics_test.go
Josh Bleecher Snyder 94fb42d4b2 all: use testingutil.MinAllocsPerRun
There are a few remaining uses of testing.AllocsPerRun:
Two in which we only log the number of allocations,
and one in which dynamically calculate the allocations
target based on a different AllocsPerRun run.

This also allows us to tighten the "no allocs"
test in wgengine/filter.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2021-10-28 12:48:37 -07:00

54 lines
1000 B
Go

// Copyright (c) 2021 Tailscale Inc & 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 metrics
import (
"os"
"runtime"
"testing"
"tailscale.com/tstest"
)
func TestCurrentFileDescriptors(t *testing.T) {
if runtime.GOOS != "linux" {
t.Skipf("skipping on %v", runtime.GOOS)
}
n := CurrentFDs()
if n < 3 {
t.Fatalf("got %v; want >= 3", n)
}
err := tstest.MinAllocsPerRun(t, 0, func() {
n = CurrentFDs()
})
if err != nil {
t.Fatal(err)
}
// Open some FDs.
const extra = 10
for i := 0; i < extra; i++ {
f, err := os.Open("/proc/self/stat")
if err != nil {
t.Fatal(err)
}
defer f.Close()
t.Logf("fds for #%v = %v", i, CurrentFDs())
}
n2 := CurrentFDs()
if n2 < n+extra {
t.Errorf("fds changed from %v => %v, want to %v", n, n2, n+extra)
}
}
func BenchmarkCurrentFileDescriptors(b *testing.B) {
b.ReportAllocs()
for i := 0; i < b.N; i++ {
_ = CurrentFDs()
}
}