Begin implementing EC balancing parallelization support. (#6342)

* Begin implementing EC balancing parallelization support.

Impacts both `ec.encode` and `ec.balance`,

* Nit: improve type naming.

* Make the goroutine workgroup handler for `EcBalance()` a bit smarter/error-proof.

* Nit: unify naming for `ecBalancer` wait group methods with the rest of the module.

* Fix concurrency bug.

* Fix whitespace after Gitlab automerge.

* Delete stray TODO.

1 files changed, 2 insertions, 2 deletions

diff --git a/weed/shell/command_ec_balance.go b/weed/shell/command_ec_balance.go
index 9e27f40ce..31782b279 100644
--- a/weed/shell/command_ec_balance.go
+++ b/weed/shell/command_ec_balance.go
@@ -17,7 +17,6 @@ func (c *commandEcBalance) Name() string {
 	return "ec.balance"
 }
 
-// TODO: Update help string and move to command_ec_common.go once shard replica placement logic is enabled.
 func (c *commandEcBalance) Help() string {
 	return `balance all ec shards among all racks and volume servers
 
@@ -36,6 +35,7 @@ func (c *commandEcBalance) Do(args []string, commandEnv *CommandEnv, writer io.W
 	collection := balanceCommand.String("collection", "EACH_COLLECTION", "collection name, or \"EACH_COLLECTION\" for each collection")
 	dc := balanceCommand.String("dataCenter", "", "only apply the balancing for this dataCenter")
 	shardReplicaPlacement := balanceCommand.String("shardReplicaPlacement", "", "replica placement for EC shards, or master default if empty")
+	parallelize := balanceCommand.Bool("parallelize", true, "parallelize operations whenever possible")
 	applyBalancing := balanceCommand.Bool("force", false, "apply the balancing plan")
 	if err = balanceCommand.Parse(args); err != nil {
 		return nil
@@ -62,5 +62,5 @@ func (c *commandEcBalance) Do(args []string, commandEnv *CommandEnv, writer io.W
 		return err
 	}
 
-	return EcBalance(commandEnv, collections, *dc, rp, *applyBalancing)
+	return EcBalance(commandEnv, collections, *dc, rp, *parallelize, *applyBalancing)
 }