Lately I've been noticing odd errors with the OSGeo wiki; I examined this closely (it took me a very long time to find the cause) - it was in fact 'no space left on device', but in this case it was a full 'inodes' or deleted files. I noticed that there were 800000+ temporary session files living in /tmp. I cleaned that and we now have inodes/temporary space for files/processes.
Hoping everyone has a nice Thursday.
-jeff