From 5a2ff6af888ff76a2895a0fe453c1613996edd8b Mon Sep 17 00:00:00 2001
From: AlexStocks <alexstocks@foxmail.com>
Date: Tue, 19 Oct 2021 22:12:25 +0800
Subject: [PATCH] release large buffer

---
 bytes/buffer.go | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/bytes/buffer.go b/bytes/buffer.go
index 623f88e..6d876df 100644
--- a/bytes/buffer.go
+++ b/bytes/buffer.go
@@ -149,11 +149,13 @@ func (b *Buffer) grow(n int) int {
 	}
 	c := cap(b.buf)
 	if n <= c/2-m {
-		// We can slide things down instead of allocating a new
-		// slice. We only need m+n <= c to slide, but
-		// we instead let capacity get twice as large so we
-		// don't spend all our time copying.
-		copy(b.buf, b.buf[b.off:])
+		// decrease buffer space
+		bufLen := len(b.buf[b.off:]) + n
+		if bufLen < smallBufferSize {
+			bufLen = smallBufferSize
+		}
+		newBuf := make([]byte, 0, bufLen)
+		b.buf = append(newBuf, b.buf[b.off:]...)
 	} else if c > maxInt-c-n {
 		panic(ErrTooLarge)
 	} else {