From 145759f6ed2fb7ceefa640a1a7215099746d41ba Mon Sep 17 00:00:00 2001
From: Andrew Laski <andrew.laski@rackspace.com>
Date: Thu, 14 Feb 2013 17:02:06 -0500
Subject: [xenapi] Cooperatively yield during sparse copy

On a resize down the sparse copy blocks other operations from running on
the compute node, and can take a long time to finish.  This patch adds a
greenthread yield to not block other things from happening on the
compute node.

Change-Id: I1287a6a0bb3157ad0e5eafe53b02db21849650fa
---
 nova/virt/xenapi/vm_utils.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/nova/virt/xenapi/vm_utils.py b/nova/virt/xenapi/vm_utils.py
index 97e9e87f8..3bfe6de09 100644
--- a/nova/virt/xenapi/vm_utils.py
+++ b/nova/virt/xenapi/vm_utils.py
@@ -2083,6 +2083,7 @@ def _sparse_copy(src_path, dst_path, virtual_size, block_size=4096):
                             break
 
                         data = src.read(min(block_size, left))
+                        greenthread.sleep(0)
 
     duration = time.time() - start_time
     compression_pct = float(skipped_bytes) / bytes_read * 100
-- 
cgit