[system test] rebalance failed due to memcached on added node crashed

Install couchbase server 2.0.1-185 on 4 physical servers with 2 separated disks
Create a cluster with 3 nodes
10.2.1.61
10.2.1.62
10.2.1.63
Create 2 buckets: default (14GB) and sasl (10GB)
No view or xdcr created
Load 20+ million items to both bucket until resident ratio on both bucket around 90%
Access cluster in 3 hours with spec in this page http://hub.internal.couchbase.com/confluence/pages/viewpage.action?pageId=6785119
Add node 10.2.1.64 to cluster and rebalance.
Rebalance failed with error

Rebalance exited with reason {unexpected_exit,
{'EXIT',<0.28651.49>,
{{badmatch,[

{<20943.32282.9>,noproc}]},
[{misc, sync_shutdown_many_i_am_trapping_exits,1}, {misc,try_with_maybe_ignorant_after,2}, {gen_server,terminate,6}, {proc_lib,init_p_do_apply,3}]}}}
ns_orchestrator002 ns_1@10.2.1.61 18:16:19 - Fri Mar 29, 2013
<0.28617.49> exited with {unexpected_exit,
{'EXIT',<0.28651.49>,
{{badmatch,[{<20943.32282.9>,noproc}

]},
[

{misc, sync_shutdown_many_i_am_trapping_exits, 1}

,

{misc,try_with_maybe_ignorant_after,2}

,

{gen_server,terminate,6}

,

{proc_lib,init_p_do_apply,3}

]}}} ns_vbucket_mover000 ns_1@10.2.1.61 18:16:18 - Fri Mar 29, 2013
Control connection to memcached on 'ns_1@10.2.1.64' disconnected: {badmatch,
{error,
closed}} ns_memcached004 ns_1@10.2.1.64 18:16:14 - Fri Mar 29, 2013
Port server memcached on node 'ns_1@10.2.1.64' exited with status 255. Restarting. Messages: Fri Mar 29 18:16:10.684162 Pacific Daylight Time 3: Fatal error in persisting DELETE ``5921A42BFC18C32EC6E223A3'' on vb 98!!! Requeue it...
Fri Mar 29 18:16:10.684162 Pacific Daylight Time 3: Fatal error in persisting DELETE ``5AFE76C1A82ABEF54B14E9FA'' on vb 98!!! Requeue it...
Fri Mar 29 18:16:10.684162 Pacific Daylight Time 3: Fatal error in persisting DELETE ``5DC7BEB033392DD5BECAE57C'' on vb 98!!! Requeue it...
Fri Mar 29 18:16:10.684162 Pacific Daylight Time 3: Fatal error in persisting DELETE ``6156CF15B5109B7AB88829EF'' on vb 98!!! Requeue it...
Fri Mar 29 18:16:10.684162 Pacific Daylight Time 3: Fatal error in persisti

Link to manifest file of this build http://builds.hq.northscale.net/latestbuilds/couchbase-server-community_x86_64_2.0.1-185-rel.setup.exe.manifest.xml

Link to collect info of all nodes https://s3.amazonaws.com/packages.couchbase/collect_info/2_0_1/201304/4phy-win-201_185-reb-failed-disk-write-failed-20130401-114233.tgz