func newBucketMetacache(bucket string, cleanup bool) *bucketMetacache {
	if cleanup {
		// Recursively delete all caches.
		objAPI := newObjectLayerFn()
		if objAPI != nil {
			ez, ok := objAPI.(deleteAllStorager)
			if ok {
				ctx := context.Background()
				ez.deleteAll(ctx, minioMetaBucket, metacachePrefixForID(bucket, slashSeparator))
			}
		}
	}
	return &bucketMetacache{
		bucket:     bucket,