proxy: use buffer pool to copy response

``` name old time/op new time/op delta CopyStream/size_100-8 2.37µs ± 1% 0.07µs ± 3% -97.09% (p=0.000 n=9+10) CopyStream/size_1000-8 2.38µs ± 2% 0.07µs ± 6% -97.04% (p=0.000 n=10+10) CopyStream/size_10000-8 2.38µs ± 1% 0.07µs ± 7% -97.09% (p=0.000 n=10+10) CopyStream/size_100000-8 2.45µs ± 1% 0.07µs ± 1% -97.20% (p=0.000 n=10+10) CopyStream/size_1000000-8 2.54µs ± 2% 0.07µs ± 2% -97.29% (p=0.000 n=9+10) CopyStream/size_10000000-8 2.60µs ± 6% 0.07µs ± 2% -97.35% (p=0.000 n=10+10) name old alloc/op new alloc/op delta CopyStream/size_100-8 8.21kB ± 0% 0.02kB ± 0% -99.81% (p=0.000 n=10+10) CopyStream/size_1000-8 8.21kB ± 0% 0.02kB ± 0% -99.81% (p=0.000 n=10+10) CopyStream/size_10000-8 8.21kB ± 0% 0.02kB ± 0% -99.81% (p=0.000 n=10+10) CopyStream/size_100000-8 8.21kB ± 0% 0.02kB ± 0% -99.81% (p=0.000 n=10+10) CopyStream/size_1000000-8 8.21kB ± 0% 0.02kB ± 0% -99.81% (p=0.000 n=10+10) CopyStream/size_10000000-8 8.21kB ± 0% 0.02kB ± 0% -99.81% (p=0.000 n=10+10) name old allocs/op new allocs/op delta CopyStream/size_100-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) CopyStream/size_1000-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) CopyStream/size_10000-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) CopyStream/size_100000-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) CopyStream/size_1000000-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) CopyStream/size_10000000-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10) ``` Signed-off-by: Alexander Yastrebov <alexander.yastrebov@zalando.de>
zalando · Feb 10, 2023 · 0fdda80 · 0fdda80
1 parent f74b863
commit 0fdda80
Showing 1 changed file with 11 additions and 2 deletions.
diff --git a/proxy/proxy.go b/proxy/proxy.go
@@ -17,6 +17,7 @@ import (
 	"runtime"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 	"unicode/utf8"
 
@@ -425,10 +426,18 @@ func (f *flusher) Write(p []byte) (n int, err error) {
 	return
 }
 
+var bufPool = sync.Pool{
+	New: func() any {
+		b := make([]byte, proxyBufferSize)
+		return &b
+	},
+}
+
 func copyStream(to flushWriter, from io.Reader) (int64, error) {
-	b := make([]byte, proxyBufferSize)
+	b := bufPool.Get().(*[]byte)
+	defer bufPool.Put(b)
 
-	return io.CopyBuffer(&flusher{to}, from, b)
+	return io.CopyBuffer(&flusher{to}, from, *b)
 }
 
 func schemeFromRequest(r *http.Request) string {