support concurrent ec.decode

weed/shell/command_ec_decode.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"github.com/seaweedfs/seaweedfs/weed/pb"
 	"github.com/seaweedfs/seaweedfs/weed/storage/types"
+	"golang.org/x/sync/errgroup"
 	"io"
 	"time"
 
@@ -41,6 +42,7 @@ func (c *commandEcDecode) Do(args []string, commandEnv *CommandEnv, writer io.Wr
 	decodeCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
 	volumeId := decodeCommand.Int("volumeId", 0, "the volume id")
 	collection := decodeCommand.String("collection", "", "the collection name")
+	concurrency := decodeCommand.Int("concurrency", 0, "number of parallel ec decode threads")
 	if err = decodeCommand.Parse(args); err != nil {
 		return nil
 	}
@@ -65,13 +67,18 @@ func (c *commandEcDecode) Do(args []string, commandEnv *CommandEnv, writer io.Wr
 	// apply to all volumes in the collection
 	volumeIds := collectEcShardIds(topologyInfo, *collection)
 	fmt.Printf("ec encode volumes: %v\n", volumeIds)
-	for _, vid := range volumeIds {
+	eg, _ := errgroup.WithContext(context.Background())
+	eg.SetLimit(*concurrency)
+	for _, _vid := range volumeIds {
+		vid := _vid
+		eg.Go(func() error {
 			if err = doEcDecode(commandEnv, topologyInfo, *collection, vid); err != nil {
 				return err
 			}
-	}
-
 			return nil
+		})
+	}
+	return eg.Wait()
 }
 
 func doEcDecode(commandEnv *CommandEnv, topoInfo *master_pb.TopologyInfo, collection string, vid needle.VolumeId) (err error) {