TAP UniXDCR (xmem mode), time taken by ep_queue_size to 0 is significant

[Jenkins]
http://qa.hq.northscale.net/job/centos_x64--31_01--uniXDCR-P1/29/consoleFull

[Test]
./testrunner -i /tmp/ubuntu-64-2.0-uniXDCR.ini GROUP=CHAIN,num_items=50000,get-cbcollect-info=True -t xdcr.uniXDCR.unidirectional.load_with_async_ops,items=100000,rdirection=unidirection,ctopology=chain,doc-ops=update-delete,sasl_buckets=1,replication_type=xmem,GROUP=CHAIN;P0;xmem

[Test Logs]
2014-04-18 02:55:39 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 1748 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:55:41 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 1907 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:55:44 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 1478 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:55:46 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 1569 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:55:49 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 975 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:55:51 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 898 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:55:54 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 202 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:55:56 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 91 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:55:59 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:01 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:04 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:06 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:09 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:11 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:14 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:16 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:19 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:21 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:24 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:26 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:29 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:32 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:35 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:37 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:40 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:42 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:45 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:47 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:50 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:52 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:56:55 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
2014-04-18 02:56:57 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 43 == 0 expected on '10.3.121.65:8091', default bucket
2014-04-18 02:57:00 | WARNING | MainProcess | Cluster_Thread | [task.check] Not Ready: ep_queue_size 4 == 0 expected on '10.3.121.65:8091', sasl_bucket_1 bucket
ERROR
[('testrunner', 331, '<module>', 'result = unittest.TextTestRunner(verbosity=2).run(suite)'), ('/usr/lib/python2.7/unittest/runner.py', 151, 'run', 'test(result)'), ('/usr/lib/python2.7/unittest/suite.py', 70, '__call__', 'return self.run(*args, **kwds)'), ('/usr/lib/python2.7/unittest/suite.py', 108, 'run', 'test(result)'), ('/usr/lib/python2.7/unittest/case.py', 391, '__call__', 'return self.run(*args, **kwds)'), ('/usr/lib/python2.7/unittest/case.py', 327, 'run', 'testMethod()'), ('pytests/xdcr/uniXDCR.py', 42, 'load_with_async_ops', 'self._wait_for_stats_all_buckets(self.src_nodes)'), ('pytests/xdcr/xdcrbasetests.py', 1241, '_wait_for_stats_all_buckets', 'is_verified = self._poll_for_condition(verify)'), ('pytests/xdcr/xdcrbasetests.py', 901, '_poll_for_condition', 'return self._poll_for_condition_rec(condition, interval, num_itr)'), ('pytests/xdcr/xdcrbasetests.py', 907, '_poll_for_condition_rec', 'if condition():'), ('pytests/xdcr/xdcrbasetests.py', 1234, 'verify', 'task.result(timeout)'), ('lib/tasks/future.py', 162, 'result', 'self.set_exception(TimeoutError())'), ('lib/tasks/future.py', 264, 'set_exception', 'print traceback.extract_stack()')]
Fri Apr 18 02:57:01 2014

[Test Steps]
1. Create 4-4 Nodes SRC and DEST.
2. Create 1 sasl, 1 default bucket.
3. Configure XMEM Uni XDCR for both buckets.
4. Load 1M Items each bucket.
5. Update 30%, delete 30% items on each bucket.
6. Wait for stats ep_queue_size to 0 -> Timeout here.