chore(buffers): Set the default read/write buffer size of Redis connection to 32KiB (#3483)

* update README.md

Signed-off-by: Xiaolong Chen <fukua95@gmail.com>

* typo: 0.5MiB -> 256KiB

Signed-off-by: Xiaolong Chen <fukua95@gmail.com>

* Set the default read/write buffer size of Redis connection to 32KiB

Signed-off-by: Xiaolong Chen <fukua95@gmail.com>

---------

Signed-off-by: Xiaolong Chen <fukua95@gmail.com>

Author: cxljs

README.md

@@ -301,7 +301,7 @@ func main() {
 
 ### Buffer Size Configuration
 
-go-redis uses 0.5MiB read and write buffers by default for optimal performance. For high-throughput applications or large pipelines, you can customize buffer sizes:
+go-redis uses 32KiB read and write buffers by default for optimal performance. For high-throughput applications or large pipelines, you can customize buffer sizes:
 
 ```go
 rdb := redis.NewClient(&redis.Options{
@@ -376,7 +376,7 @@ You can find further details in the [query dialect documentation](https://redis.
 
 #### Custom buffer sizes
 Prior to v9.12, the buffer size was the default go value of 4096 bytes. Starting from v9.12, 
-go-redis uses 256KiB read and write buffers by default for optimal performance.
+go-redis uses 32KiB read and write buffers by default for optimal performance.
 For high-throughput applications or large pipelines, you can customize buffer sizes:
 
 ```go

internal/pool/buffer_size_test.go

@@ -34,12 +34,12 @@ var _ = Describe("Buffer Size Configuration", func() {
 		Expect(err).NotTo(HaveOccurred())
 		defer connPool.CloseConn(cn)
 
-		// Check that default buffer sizes are used (256KiB)
+		// Check that default buffer sizes are used (32KiB)
 		writerBufSize := getWriterBufSizeUnsafe(cn)
 		readerBufSize := getReaderBufSizeUnsafe(cn)
 
-		Expect(writerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 256KiB buffer size
-		Expect(readerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 256KiB buffer size
+		Expect(writerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 32KiB buffer size
+		Expect(readerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 32KiB buffer size
 	})
 
 	It("should use custom buffer sizes when specified", func() {
@@ -79,28 +79,28 @@ var _ = Describe("Buffer Size Configuration", func() {
 		Expect(err).NotTo(HaveOccurred())
 		defer connPool.CloseConn(cn)
 
-		// Check that default buffer sizes are used (256KiB)
+		// Check that default buffer sizes are used (32KiB)
 		writerBufSize := getWriterBufSizeUnsafe(cn)
 		readerBufSize := getReaderBufSizeUnsafe(cn)
 
-		Expect(writerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 256KiB buffer size
-		Expect(readerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 256KiB buffer size
+		Expect(writerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 32KiB buffer size
+		Expect(readerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 32KiB buffer size
 	})
 
-	It("should use 256KiB default buffer sizes for standalone NewConn", func() {
-		// Test that NewConn (without pool) also uses 256KiB buffers
+	It("should use 32KiB default buffer sizes for standalone NewConn", func() {
+		// Test that NewConn (without pool) also uses 32KiB buffers
 		netConn := newDummyConn()
 		cn := pool.NewConn(netConn)
 		defer cn.Close()
 
 		writerBufSize := getWriterBufSizeUnsafe(cn)
 		readerBufSize := getReaderBufSizeUnsafe(cn)
 
-		Expect(writerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 256KiB buffer size
-		Expect(readerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 256KiB buffer size
+		Expect(writerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 32KiB buffer size
+		Expect(readerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 32KiB buffer size
 	})
 
-	It("should use 256KiB defaults even when pool is created directly without buffer sizes", func() {
+	It("should use 32KiB defaults even when pool is created directly without buffer sizes", func() {
 		// Test the scenario where someone creates a pool directly (like in tests)
 		// without setting ReadBufferSize and WriteBufferSize
 		connPool = pool.NewConnPool(&pool.Options{
@@ -114,12 +114,12 @@ var _ = Describe("Buffer Size Configuration", func() {
 		Expect(err).NotTo(HaveOccurred())
 		defer connPool.CloseConn(cn)
 
-		// Should still get 256KiB defaults because NewConnPool sets them
+		// Should still get 32KiB defaults because NewConnPool sets them
 		writerBufSize := getWriterBufSizeUnsafe(cn)
 		readerBufSize := getReaderBufSizeUnsafe(cn)
 
-		Expect(writerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 256KiB buffer size
-		Expect(readerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 256KiB buffer size
+		Expect(writerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 32KiB buffer size
+		Expect(readerBufSize).To(Equal(proto.DefaultBufferSize)) // Default 32KiB buffer size
 	})
 })
 

internal/pool/conn.go

@@ -37,11 +37,11 @@ func NewConnWithBufferSize(netConn net.Conn, readBufSize, writeBufSize int) *Con
 		createdAt: time.Now(),
 	}
 
-	// Use specified buffer sizes, or fall back to 0.5MiB defaults if 0
+	// Use specified buffer sizes, or fall back to 32KiB defaults if 0
 	if readBufSize > 0 {
 		cn.rd = proto.NewReaderSize(netConn, readBufSize)
 	} else {
-		cn.rd = proto.NewReader(netConn) // Uses 0.5MiB default
+		cn.rd = proto.NewReader(netConn) // Uses 32KiB default
 	}
 
 	if writeBufSize > 0 {

internal/proto/reader.go

@@ -12,8 +12,8 @@ import (
 	"github.com/redis/go-redis/v9/internal/util"
 )
 
-// DefaultBufferSize is the default size for read/write buffers (256 KiB).
-const DefaultBufferSize = 256 * 1024
+// DefaultBufferSize is the default size for read/write buffers (32 KiB).
+const DefaultBufferSize = 32 * 1024
 
 // redis resp protocol data type.
 const (

options.go

@@ -135,14 +135,14 @@ type Options struct {
 	// Larger buffers can improve performance for commands that return large responses.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	ReadBufferSize int
 
 	// WriteBufferSize is the size of the bufio.Writer buffer for each connection.
 	// Larger buffers can improve performance for large pipelines and commands with many arguments.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	WriteBufferSize int
 
 	// PoolFIFO type of connection pool.

osscluster.go

@@ -96,14 +96,14 @@ type ClusterOptions struct {
 	// Larger buffers can improve performance for commands that return large responses.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	ReadBufferSize int
 
 	// WriteBufferSize is the size of the bufio.Writer buffer for each connection.
 	// Larger buffers can improve performance for large pipelines and commands with many arguments.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	WriteBufferSize int
 
 	TLSConfig *tls.Config

ring.go

@@ -128,14 +128,14 @@ type RingOptions struct {
 	// Larger buffers can improve performance for commands that return large responses.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	ReadBufferSize int
 
 	// WriteBufferSize is the size of the bufio.Writer buffer for each connection.
 	// Larger buffers can improve performance for large pipelines and commands with many arguments.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	WriteBufferSize int
 
 	TLSConfig *tls.Config

sentinel.go

@@ -94,14 +94,14 @@ type FailoverOptions struct {
 	// Larger buffers can improve performance for commands that return large responses.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	ReadBufferSize int
 
 	// WriteBufferSize is the size of the bufio.Writer buffer for each connection.
 	// Larger buffers can improve performance for large pipelines and commands with many arguments.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	WriteBufferSize int
 
 	PoolFIFO bool

universal.go

@@ -65,14 +65,14 @@ type UniversalOptions struct {
 	// Larger buffers can improve performance for commands that return large responses.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	ReadBufferSize int
 
 	// WriteBufferSize is the size of the bufio.Writer buffer for each connection.
 	// Larger buffers can improve performance for large pipelines and commands with many arguments.
 	// Smaller buffers can improve memory usage for larger pools.
 	//
-	// default: 256KiB (262144 bytes)
+	// default: 32KiB (32768 bytes)
 	WriteBufferSize int
 
 	// PoolFIFO uses FIFO mode for each node connection pool GET/PUT (default LIFO).