fix: optimize listMultipartUploads to serve via local disks (#18034)

and remove unused getLoadBalancedDisks()

cmd/erasure-common.go

@@ -74,62 +74,6 @@ func (er erasureObjects) getLoadBalancedLocalDisks() (newDisks []StorageAPI) {
 	return newDisks
 }
 
-// getLoadBalancedDisks - fetches load balanced (sufficiently randomized) disk slice.
-// ensures to skip disks if they are not healing and online.
-func (er erasureObjects) getLoadBalancedDisks(optimized bool) []StorageAPI {
-	disks := er.getDisks()
-
-	r := rand.New(rand.NewSource(time.Now().UnixNano()))
-	if !optimized {
-		var newDisks []StorageAPI
-		for _, i := range r.Perm(len(disks)) {
-			newDisks = append(newDisks, disks[i])
-		}
-		return newDisks
-	}
-
-	var wg sync.WaitGroup
-	var mu sync.Mutex
-	newDisks := map[uint64][]StorageAPI{}
-	// Based on the random shuffling return back randomized disks.
-	for _, i := range r.Perm(len(disks)) {
-		i := i
-		wg.Add(1)
-		go func() {
-			defer wg.Done()
-			if disks[i] == nil {
-				return
-			}
-			di, err := disks[i].DiskInfo(context.Background(), false)
-			if err != nil || di.Healing {
-				// - Do not consume disks which are not reachable
-				//   unformatted or simply not accessible for some reason.
-				//
-				// - Do not consume disks which are being healed
-				//
-				// - Future: skip busy disks
-				return
-			}
-
-			mu.Lock()
-			// Capture disks usage wise upto resolution of MiB
-			newDisks[di.Used/1024/1024] = append(newDisks[di.Used/1024/1024], disks[i])
-			mu.Unlock()
-		}()
-	}
-	wg.Wait()
-
-	var max uint64
-	for k := range newDisks {
-		if k > max {
-			max = k
-		}
-	}
-
-	// Return disks which have maximum disk usage common.
-	return newDisks[max]
-}
-
 // readMultipleFiles Reads raw data from all specified files from all disks.
 func readMultipleFiles(ctx context.Context, disks []StorageAPI, req ReadMultipleReq, readQuorum int) ([]ReadMultipleResp, error) {
 	resps := make([]chan ReadMultipleResp, len(disks))

cmd/erasure-multipart.go

@@ -269,7 +269,13 @@ func (er erasureObjects) ListMultipartUploads(ctx context.Context, bucket, objec
 
 	var uploadIDs []string
 	var disk StorageAPI
-	for _, disk = range er.getLoadBalancedDisks(true) {
+	disks := er.getLoadBalancedLocalDisks()
+	if len(disks) == 0 {
+		// using er.getLoadBalancedLocalDisks() has one side-affect where
+		// on a pooled setup all disks are remote, add a fallback
+		disks = er.getOnlineDisks()
+	}
+	for _, disk = range disks {
 		uploadIDs, err = disk.ListDir(ctx, minioMetaMultipartBucket, er.getMultipartSHADir(bucket, object), -1)
 		if err != nil {
 			if errors.Is(err, errDiskNotFound) {