Illumos 4873 - zvol unmap calls can take a very long time for larger datasets

4873 zvol unmap calls can take a very long time for larger datasets
Author: Alex Reece <[email protected]>
Reviewed by: George Wilson <[email protected]>
Reviewed by: Matthew Ahrens <[email protected]>
Reviewed by: Paul Dagnelie <[email protected]>
Reviewed by: Basil Crow <[email protected]>
Reviewed by: Dan McDonald <[email protected]>
Approved by: Robert Mustacchi <[email protected]>

References:
  https://www.illumos.org/issues/4873
  https://github.com/illumos/illumos-gate/commit/0f6d88a

Porting Notes:

dbuf_free_range():
  - reduce stack usage using kmem_alloc()
  - the sorted AVL tree will handle the spill block case correctly
    without all the special handling in the for() loop

Ported-by: Chris Dunlop <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/sys/avl.h b/include/sys/avl.h
index ba305c908..9bc2b4a32 100644
--- a/include/sys/avl.h
+++ b/include/sys/avl.h
@@ -23,6 +23,10 @@
  * Use is subject to license terms.
  */
 
+/*
+ * Copyright (c) 2014 by Delphix. All rights reserved.
+ */
+
 #ifndef	_AVL_H
 #define	_AVL_H
 
@@ -260,6 +264,11 @@ extern boolean_t avl_update_lt(avl_tree_t *, void *);
 extern boolean_t avl_update_gt(avl_tree_t *, void *);
 
 /*
+ * Swaps the contents of the two trees.
+ */
+extern void avl_swap(avl_tree_t *tree1, avl_tree_t *tree2);
+
+/*
  * Return the number of nodes in the tree
  */
 extern ulong_t avl_numnodes(avl_tree_t *tree);