Commit 3ead4998 authored by Brad Fitzpatrick's avatar Brad Fitzpatrick

cmd/dist: skip compiling 100 packages without benchmarks in race mode

The go_test_bench:* tests run:

    go test -short -race -run=^$ -benchtime=.1s -cpu=4 $PKG

... on each discovered package with any tests. (The same set used for
the "go_test:*" tests)

That set was 168 packages:

$ go tool dist test -list | grep go_test: | wc -l
168

But only 76 of those have a "func Benchmark", and running each
"go_test_bench:" test and compiling it in race mode, just to do
nothing took 1-2 seconds each.

So stop doing that and filter out the useless packages earlier. Now:

$ go tool dist test -list -race | grep go_test_bench:  | wc -l
76

Should save 90-180 seconds. (or maybe 45 seconds for trybots, since
they're sharded)

Updates #17104

Change-Id: I08ccb072a0dc0454ea425540ee8e74b59f83b773
Reviewed-on: https://go-review.googlesource.com/29153
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: default avatarIan Lance Taylor <iant@golang.org>
parent 059ada59
......@@ -9,6 +9,7 @@ import (
"errors"
"flag"
"fmt"
"io/ioutil"
"log"
"os"
"os/exec"
......@@ -361,7 +362,9 @@ func (t *tester) registerTests() {
}
if t.race {
for _, pkg := range pkgs {
t.registerRaceBenchTest(pkg)
if t.packageHasBenchmarks(pkg) {
t.registerRaceBenchTest(pkg)
}
}
}
}
......@@ -1086,3 +1089,38 @@ var cgoPackages = []string{
"net",
"os/user",
}
var funcBenchmark = []byte("\nfunc Benchmark")
// packageHasBenchmarks reports whether pkg has benchmarks.
// On any error, it conservatively returns true.
//
// This exists just to eliminate work on the builders, since compiling
// a test in race mode just to discover it has no benchmarks costs a
// second or two per package, and this function returns false for
// about 100 packages.
func (t *tester) packageHasBenchmarks(pkg string) bool {
pkgDir := filepath.Join(t.goroot, "src", pkg)
d, err := os.Open(pkgDir)
if err != nil {
return true // conservatively
}
defer d.Close()
names, err := d.Readdirnames(-1)
if err != nil {
return true // conservatively
}
for _, name := range names {
if !strings.HasSuffix(name, "_test.go") {
continue
}
slurp, err := ioutil.ReadFile(filepath.Join(pkgDir, name))
if err != nil {
return true // conservatively
}
if bytes.Contains(slurp, funcBenchmark) {
return true
}
}
return false
}
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment