3740 Poor ZFS send / receive performance due to snapshot hold / release processing
Submitted by: Steven Hartland <steven.hartland@multiplay.co.uk>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>

@@ -19,10 +19,11 @@
  * CDDL HEADER END
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2013 Steven Hartland. All rights reserved.
  */
 
 #include <sys/zfs_context.h>
 #include <sys/dsl_userhold.h>
 #include <sys/dsl_dataset.h>

@@ -125,10 +126,14 @@
         }
 
         pair = nvlist_next_nvpair(dsda->dsda_errlist, NULL);
         if (pair != NULL)
                 return (fnvpair_value_int32(pair));
+
+        if (nvlist_empty(dsda->dsda_successful_snaps))
+                return (SET_ERROR(ENOENT));
+
         return (0);
 }
 
 struct process_old_arg {
         dsl_dataset_t *ds;