From b352133b3cfcde8afeb58127bf01d31735faa2fe Mon Sep 17 00:00:00 2001
From: Eugene Blikh <bigbes@gmail.com>
Date: Sun, 16 Aug 2026 07:56:07 +0300
Subject: [PATCH] bearer: silence the std logger the benchmarks were timing
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sr-ht-core's auth.DecodeBearerToken calls log.Printf on every token it
refuses, so BenchmarkValidate/invalid wrote one line per iteration. The cost
was not the file: log.Printf takes a mutex, and the case reported 925 ns/op
where the work is 92.5.

The file was a hazard too. An unfiltered run of this package produced 9.5
million lines and 901 MB, and benchfmt skips what it cannot parse — so
bench.sr.ht would have accepted that upload and reported success over it.

Ignore cover.out and bench.txt: make cover and make bench write them into
the checkout.
---
 .gitignore                  |  2 ++
 bearer/bearer_bench_test.go | 27 +++++++++++++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/.gitignore b/.gitignore
index 673cd2135443792323ed326f3dd5dfeec97a6624..c7b4858b6bdc96131fd0a6974e605980cc131bb4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,3 +11,5 @@
 *.db
 .beads-credential-key
 .beads/proxieddb/
+cover.out
+bench.txt
diff --git a/bearer/bearer_bench_test.go b/bearer/bearer_bench_test.go
index d5c9915f36e95259699f7a7bd074e6c58ba76ecb..18c3249b72f6831b948c8233094ad31a24f67936 100644
--- a/bearer/bearer_bench_test.go
+++ b/bearer/bearer_bench_test.go
@@ -3,11 +3,32 @@ package bearer
 import (
 	"context"
 	"errors"
+	"io"
+	"log"
 	"net/http"
 	"net/http/httptest"
 	"testing"
 )
 
+// discardStdLog silences the standard logger for one benchmark. sr-ht-core's
+// auth.DecodeBearerToken calls log.Printf on every token it refuses, so the
+// invalid case below writes one line per iteration — an unfiltered run of this
+// package produced 9.5 million of them and a 901 MB file. Two things follow.
+// The number stops being a measurement of this package: log.Printf takes a
+// mutex, so what was timed was the logger. And the file is worse than useless
+// rather than merely large, because benchfmt skips lines it cannot parse, so
+// bench.sr.ht would accept that upload and report success over it.
+//
+// It is the std log package here rather than slog — that is why this is not
+// the discardLog the middleware and chimw benchmarks share.
+func discardStdLog(b *testing.B) {
+	b.Helper()
+
+	previous := log.Writer()
+	log.SetOutput(io.Discard)
+	b.Cleanup(func() { log.SetOutput(previous) })
+}
+
 // The grant strings these benchmarks present. The stateless one is what a short
 // token carries; the registered one adds the id: member that turns step 4 from
 // a no-op into a cache lookup.
@@ -74,6 +95,8 @@ func benchValidator(b *testing.B) *Validator {
 //     the path an instance under a flood of forged credentials runs; it must
 //     stay the cheapest thing here.
 func BenchmarkValidate(b *testing.B) {
+	discardStdLog(b)
+
 	ctx := context.Background()
 	v := benchValidator(b)
 
@@ -136,6 +159,8 @@ func BenchmarkValidate(b *testing.B) {
 // beside BenchmarkValidate/stateless — the gap is the grant check that Inspect
 // leaves to the handler.
 func BenchmarkInspect(b *testing.B) {
+	discardStdLog(b)
+
 	ctx := context.Background()
 	v := benchValidator(b)
 	presented := ourToken(benchGrants)
@@ -158,6 +183,8 @@ func BenchmarkInspect(b *testing.B) {
 // is not, and the point of measuring it is to know which of the two dominates
 // before somebody proposes sharding the cache.
 func BenchmarkValidateParallel(b *testing.B) {
+	discardStdLog(b)
+
 	ctx := context.Background()
 	v := benchValidator(b)
 	registered := ourToken(benchGrantsRegistered)