Merge pull request from go-redis/fix/cluster-loading

Better cluster loading handling.
This commit is contained in:
Vladimir Mihailenco 2016-10-09 11:36:11 +03:00 committed by GitHub
commit 5aae583e0c
2 changed files with 26 additions and 19 deletions
cluster.go
internal/errors

View File

@ -15,6 +15,11 @@ import (
type clusterNode struct {
Client *Client
Latency time.Duration
loading time.Time
}
func (n *clusterNode) Loading() bool {
return !n.loading.IsZero() && time.Since(n.loading) < time.Minute
}
// ClusterClient is a Redis Cluster client representing a pool of zero
@ -218,10 +223,20 @@ func (c *ClusterClient) slotSlaveNode(slot int) (*clusterNode, error) {
case 1:
return nodes[0], nil
case 2:
return nodes[1], nil
if slave := nodes[1]; !slave.Loading() {
return slave, nil
}
return nodes[0], nil
default:
n := rand.Intn(len(nodes)-1) + 1
return nodes[n], nil
var slave *clusterNode
for i := 0; i < 10; i++ {
n := rand.Intn(len(nodes)-1) + 1
slave = nodes[n]
if !slave.Loading() {
break
}
}
return slave, nil
}
}
@ -287,28 +302,22 @@ func (c *ClusterClient) Process(cmd Cmder) error {
pipe := node.Client.Pipeline()
pipe.Process(NewCmd("ASKING"))
pipe.Process(cmd)
_, _ = pipe.Exec()
_, err = pipe.Exec()
pipe.Close()
ask = false
} else {
node.Client.Process(cmd)
err = node.Client.Process(cmd)
}
// If there is no (real) error, we are done!
err := cmd.Err()
// If there is no (real) error - we are done.
if err == nil {
return nil
}
// If slave is loading, read from master
if errors.IsLoading(cmd.Err()) && c.opt.ReadOnly {
trynode, err := c.slotMasterNode(slot)
if err == nil && trynode != node {
node = trynode
continue
} else {
break
}
// If slave is loading - read from master.
if c.opt.ReadOnly && errors.IsLoading(err) {
node.loading = time.Now()
continue
}
// On network errors try random node.

View File

@ -10,8 +10,6 @@ const Nil = RedisError("redis: nil")
type RedisError string
var LoadingError RedisError = "LOADING Redis is loading the dataset in memory"
func (e RedisError) Error() string { return string(e) }
func IsRetryable(err error) bool {
@ -69,5 +67,5 @@ func IsMoved(err error) (moved bool, ask bool, addr string) {
}
func IsLoading(err error) bool {
return err.Error() == string(LoadingError)
return strings.HasPrefix(err.Error(), "LOADING")
}