Fork error

[brained]

Nov 21 13:20:04 zimbra amavis[15764]: (15764-05) ESMTP> 451 4.5.0 Error in processing, id=15764-05, parts_decode_ext FAILED: run_command (open pipe): Can't fork at /usr/lib/perl5/5.8.5/i386-linux-thread-multi/IO/File.pm line 176. (Cannot allocate memory) at /opt/zimbra/amavisd/sbin/amavisd line 2145.


I'm seeing a few of these in my logs, the messages are always deferred and can be re-queued without any problem.

Is this a perl or a memory or some other problem?

top shows it's not even hitting the swap file.

[phoenix]

Are you short of memory or file descriptors?

[brained]

RAM is 1.2GB and the swap file has never been used, I'm assuming that means I've got enough RAM.

ulimit -Hn gives 1024 and ulimit -Sn gives 1024, if that's enough or not is starting to get beyond my current linux knowledge. I can see that there are no 'Too many open files' errors which seems typical for a shortage of file descriptors.

Server load is about 30 IMAP users and 10 Web users, around 800 messages per day.