Fix performance issues on write and read

- don't use the write pool to write synchronously
- add a WaitGroup on the read goroutines
- don't use the write pool (asynchronous write) by default

src/go/config/config.go

@@ -64,7 +64,7 @@ func NewRedisConf() *Redis {
 		Cluster:             false,
 		ClusterAddrs:        []string{":7001", ":7002", ":7003", ":7004", ":7005", ":7006"},
 		UseUnlink:           true,
-		UseWritePool:        true,
+		UseWritePool:        false,
 		WritePoolBufferSize: defaultWritePoolBufferSize,
 		WritePoolWorkers:    defaultWritePoolWorkers,
 	}

src/go/redisfs/client.go

@@ -87,6 +87,8 @@ func byte2StringNoCopy(b []byte) string {
 	return *(*string)(unsafe.Pointer(&b))
 }
 
+// Asynchronous writer pool
+
 // Job ...
 type Job struct {
 	async   bool
@@ -210,9 +212,9 @@ func NewWritePool(conf *config.Redis) *WritePool {
 }
 
 // SetRange ...
-func (p *WritePool) SetRange(async bool, key string, off int64, value []byte) {
+func (p *WritePool) SetRange(key string, off int64, value []byte) {
 	ack := make(chan bool) // could come from a pool instead
-	p.jobRequest <- &Job{async, key, off, value, ack}
+	p.jobRequest <- &Job{true, key, off, value, ack}
 	<-ack
 }
 
@@ -241,11 +243,21 @@ func NewFileContentClient(conf *config.Redis, stripeSize int64) *FileContentClie
 }
 
 func (c FileContentClient) writeStripe(key string, value []byte) {
-	c.writePool.SetRange(c.conf.UseWritePool, key, -1, value)
+	if c.conf.UseWritePool {
+		c.writePool.SetRange(key, -1, value)
+	} else {
+		Try(c.redisClient.Set(key, byte2StringNoCopy(value), 0).Err())
+	}
+
 }
 
 func (c FileContentClient) writeStripeAt(key string, off int64, value []byte) {
-	c.writePool.SetRange(c.conf.UseWritePool, key, off, value)
+	if c.conf.UseWritePool {
+		c.writePool.SetRange(key, off, value)
+	} else {
+		Try(c.redisClient.SetRange(key, off, byte2StringNoCopy(value)).Err())
+	}
+
 }
 
 type stripeInfo struct {
@@ -385,10 +397,12 @@ func (c FileContentClient) ReadAt(name string, off, size int64) (string, bool) {
 	ok := false
 
 	stripes := stripeLayout(c.stripeSize, off, size)
-
+	wg := sync.WaitGroup{}
+	wg.Add(len(stripes))
 	retChan := make(chan *readAtReturn, len(stripes))
 	for i, stripe := range stripes {
-		go func(key string, off, size int64, ret chan *readAtReturn, i int) {
+		go func(key string, off, size int64, ret chan *readAtReturn, i int, wg *sync.WaitGroup) {
+			defer wg.Done()
 			var s string
 			var ok bool
 			if off == 0 && size == c.stripeSize {
@@ -397,8 +411,9 @@ func (c FileContentClient) ReadAt(name string, off, size int64) (string, bool) {
 				s, ok = c.readStripeRange(key, off, off+size-1)
 			}
 			ret <- &readAtReturn{i, s, ok}
-		}(fmt.Sprintf("%s:%d", name, stripe.id), stripe.off, stripe.len, retChan, i)
+		}(fmt.Sprintf("%s:%d", name, stripe.id), stripe.off, stripe.len, retChan, i, &wg)
 	}
+	wg.Wait()
 	var i int
 	for {
 		// retrieve result and put them in order