fix: background heal to call HealFormat only if needed (#9491)

In large setups this avoids unnecessary data transfer
across nodes and potential locks.

This PR also optimizes heal result channel, which should
be avoided for each queueHealTask as its expensive
to create/close channels for large number of objects.

cmd/background-newdisks-heal-ops.go

@@ -57,6 +57,7 @@ func monitorLocalDisksAndHeal(ctx context.Context, objAPI ObjectLayer) {
 		case <-time.After(defaultMonitorNewDiskInterval):
 			// Attempt a heal as the server starts-up first.
 			localDisksInZoneHeal := make([]Endpoints, len(z.zones))
+			var healNewDisks bool
 			for i, ep := range globalEndpoints {
 				localDisksToHeal := Endpoints{}
 				for _, endpoint := range ep.Endpoints {
@@ -74,6 +75,12 @@ func monitorLocalDisksAndHeal(ctx context.Context, objAPI ObjectLayer) {
 					continue
 				}
 				localDisksInZoneHeal[i] = localDisksToHeal
+				healNewDisks = true
+			}
+
+			// Reformat disks only if needed.
+			if !healNewDisks {
+				continue
 			}
 
 			// Reformat disks