http://www.couchbase.com/issues This file is an XML representation of an issue en-us 5.2.4 845 26-12-2012 http://www.couchbase.com/issues/browse/MB-4006 Couchbase Server users are run into this issue too often which i suspect has sth to do with the uptime or maybe an unclean shutdown of the server can result in this behavior. <br/> <br/> asking customers to delete their statistics is not a very pleasent thing to do <br/> <br/> 1.7 GA MB-4006

mb_mnesia,ensure_schema timeout when restarting ns_server

Bug Critical Resolved Incomplete Public Aleksey Kondratenko Farshid Ghods 1.7.0-release-notes 1.8.0-release-notes Wed, 22 Jun 2011 11:23:45 -0500 Tue, 9 Apr 2013 12:54:13 -0500 Mon, 8 Apr 2013 18:59:01 -0500 1.7 GA 1.7.2 ns_server 1 4 When a process is killed or dies, mnesia files might be left in a poor state that prevents restart. the workaround is to remove all files under /opt/membase/var/lib/membase/mnesia/*.* fix merged reported by a user on 1.7.2 <br/> diags here : <a href="http://www63.zippyshare.com/v/19241756/file.html">http://www63.zippyshare.com/v/19241756/file.html</a> thanks for raising this again.<br/> <br/> Looks like our workaround is not working all the time. For now manual workaround of deleting mnesia files and starting ns_server again will work.<br/> <br/> For future we&#39;ll get rid of mnesia completely.<br/> Dipti, maybe I&#39;m missing something and stats-in-mnesia is not &quot;unfixable crap&quot;. But my plan since before 1.7.0 was to replace saving stats in mnesia with much simpler periodic snapshotting into plain file. Because stats are not really precious thing.<br/> <br/> I estimate this work to be around 1-2 days including thorough testing.<br/> <br/> We also had some plans for storing stats in couch, but given KISS principle I think my simplified approach is what we need.<br/> <br/> Please, decide when we want this work to be done. Let me explain &quot;not really precious thing&quot; better. Apparently it&#39;s too easily to misunderstand my original phrase as &quot;we shouldn&#39;t save stats at all&quot;. <br/> <br/> Mnesia does it&#39;s own journalling and crash recovery and durable commits and stuff like that. Or supposedly does. <br/> <br/> My point was we don&#39;t need _that_ level of durability. That means that instead of trying to commit supposedly durable transaction via mnesia after each stats sample we&#39;ll accumulate changes and save them once or twice per minute. Saving itself (because it&#39;s not much data) can be made durable and cheap. <br/> <br/> Attaching the relevant logs. Invalidated by removal of mnesia have you already removed mnesia? <br/> <br/> If so is there any impact in the upgrade process ? The code was actually ready for 2.0.1 but sadly too late. So 2.0.2 got it early.<br/> <br/> Impact on upgrade process is simple. People will lose their stats archive. I.e. we don&#39;t bother converting stats from mnesia to new format. But note that rolling upgrade already causes them to lose historical stats. Date of First Response Tue, 5 Jul 2011 14:03:00 -0500 Rank 3286 Time In Status