Some trouble compacting db file

As part of looking at MB-7824 I've found evidence of repeated compactor crashes.

Logs are available there.

Here's excerpt:

[couchdb:info,2013-02-26T14:07:27.985,ns_1@10.6.2.68:<0.5221.0>:couch_log:info:39]Starting compaction for db "MsgsCalls/4", options: []
[couchdb:info,2013-02-26T14:07:28.071,ns_1@10.6.2.68:<0.27758.32>:couch_log:info:39]Native compactor output: Compacted /data/MsgsCalls/4.couch.74 -> /data/MsgsCalls/4.couch.74.compact
[couchdb:error,2013-02-26T14:07:29.685,ns_1@10.6.2.68:<0.27758.32>:couch_log:error:42]Native compact for "MsgsCalls/4" failed due to error {error,{badmatch,{unexpected_binary,

{at,495618}

,

{wanted_bytes,2003549077}

,{got,7893081,<<100,118,114,111,122,104,105,111,115,105,99,100,115
[couchdb:info,2013-02-26T14:07:50.592,ns_1@10.6.2.68:<0.5221.0>:couch_log:info:39]Database `MsgsCalls/4` compactor died with reason: {{case_clause,
{file_already_opened,
"/data/MsgsCalls/4.couch.74.compact"}},
[

{couch_db_updater, make_target_db,2}

,

{couch_db_updater, start_copy_compact,2}

]}