Random node failures, core dump generated

I can’t see any segfault errors but last night’s problem did generate some hung-task errors in /var/log/messages. I’ve put the gist here: https://gist.github.com/stephenhenderson/91c9e431d32e1f6a3b7b (there were no other entries for over 10 minutes either side)

I think a problem in the past has been the core.dump filling up the root partition so errors might not have been written to disk successfully. This time the dump file was a bit smaller. As a side note, do you know if it’s possible to configure couchbase to specify where the memcached dump file should be written so we can direct it to another partition with more space available?

Thanks,
Stephen