bytes: Benchmark Buffer's compactions
This benchmark verifies that CL #8173043 reduces time spent
sliding the Buffer's contents.
Results without and with CL #8173043 applied:
benchmark old ns/op new ns/op delta
BenchmarkBufferFullSmallReads 755336 175054 -76.82%
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8174043
diff --git a/src/pkg/bytes/buffer_test.go b/src/pkg/bytes/buffer_test.go
index 5b0b8b5..75145b0 100644
--- a/src/pkg/bytes/buffer_test.go
+++ b/src/pkg/bytes/buffer_test.go
@@ -509,3 +509,19 @@
}
}
}
+
+// Check that we don't compact too often. From Issue 5154.
+func BenchmarkBufferFullSmallReads(b *testing.B) {
+ buf := make([]byte, 1024)
+ for i := 0; i < b.N; i++ {
+ var b Buffer
+ b.Write(buf)
+ for b.Len()+20 < b.Cap() {
+ b.Write(buf[:10])
+ }
+ for i := 0; i < 5<<10; i++ {
+ b.Read(buf[:1])
+ b.Write(buf[:1])
+ }
+ }
+}
