grpc: Enable shared write buffers by default

benchmark/benchmain/main.go

@@ -117,7 +117,7 @@ var (
 	sleepBetweenRPCs      = flags.DurationSlice("sleepBetweenRPCs", []time.Duration{0}, "Configures the maximum amount of time the client should sleep between consecutive RPCs - may be a comma-separated list")
 	connections           = flag.Int("connections", 1, "The number of connections. Each connection will handle maxConcurrentCalls RPC streams")
 	recvBufferPool        = flags.StringWithAllowedValues("recvBufferPool", recvBufferPoolSimple, "Configures the shared receive buffer pool. One of: nil, simple, all", allRecvBufferPools)
-	sharedWriteBuffer     = flags.StringWithAllowedValues("sharedWriteBuffer", toggleModeOff,
+	sharedWriteBuffer     = flags.StringWithAllowedValues("sharedWriteBuffer", toggleModeOn,
 		fmt.Sprintf("Configures both client and server to share write buffer - One of: %v", strings.Join(allToggleModes, ", ")), allToggleModes)
 
 	logger = grpclog.Component("benchmark")

dialoptions.go

@@ -705,10 +705,11 @@ func WithDisableHealthCheck() DialOption {
 func defaultDialOptions() dialOptions {
 	return dialOptions{
 		copts: transport.ConnectOptions{
-			ReadBufferSize:  defaultReadBufSize,
-			WriteBufferSize: defaultWriteBufSize,
-			UserAgent:       grpcUA,
-			BufferPool:      mem.DefaultBufferPool(),
+			ReadBufferSize:    defaultReadBufSize,
+			WriteBufferSize:   defaultWriteBufSize,
+			SharedWriteBuffer: true,
+			UserAgent:         grpcUA,
+			BufferPool:        mem.DefaultBufferPool(),
 		},
 		bs:                       internalbackoff.DefaultExponential,
 		idleTimeout:              30 * time.Minute,

server.go

@@ -189,6 +189,7 @@ var defaultServerOptions = serverOptions{
 	maxSendMessageSize:    defaultServerMaxSendMessageSize,
 	connectionTimeout:     120 * time.Second,
 	writeBufferSize:       defaultWriteBufSize,
+	sharedWriteBuffer:     true,
 	readBufferSize:        defaultReadBufSize,
 	bufferPool:            mem.DefaultBufferPool(),
 }