On Mon, Oct 5, 2009 at 10:16 AM, Chris <cjd...@brokensolstice.com> wrote: > I just reinstalled 4.5. I touched nothing on the system. I installed > mutt through pkg_add, then created a 1M empty file from /dev/null. > > I sent this email to myself thusly: mutt -a 1megfile m...@myaddress.com > </dev/null > > Same exact behavior. It spools, then I have about .5 - 1 second > before then entire system locks up.
Random guess: sendmail is one of the few standard programs that makes heavy use of fsync(). Perhaps there's something on the "deal with stuff being forced to 'disk'" paths of the xen emulation that confuses the kernel. If so, the turning off sendmail's SuperSafe option in the sendmail.cf should make things more stable. That would be *JUST* a debugging measure, as doing that on a production server, particularly one which is unstable, is a recipe for losing email. The other question is whether you've tried breaking into ddb from the console when this happens. Make sure you have ddb.console=1 in your /etc/sysctl.conf and read the ddb(4) manpage. (If xen doesn't offer console access then throw it out.) Philip Guenther