Comment 46 for bug 431040

> If log writes are an issue for you, you may want to send them elsewhere instead of killing them on reboot. (see the syslog-ng manpage, for instance, on how to do this; you can do it securely)

Thanks for that suggestion - I'll take a look. Generally I don't need persistent logs, and if there's a problem I can always temporarily make them persistent.

I have also submitted a new bug here which narrows the bug report to subdirs of /var, instead of /var itself (I did this because none of the other bug reports seem to cover this explicitly with tmpfs, and this bug has been marked "fix released" despite the whole problem not being addressed.)
https://bugs.launchpad.net/ubuntu/+source/mountall/+bug/479429