No space in available paging segments - plenty of room on HD

Question

Greetings all,
I'm running OS X Server 10.5.4 on a 2.8Ghz iMac with 4G of RAM. Every night my server crashes and reboots. The logs reveal the following:
11/21/08 2:12:02 AM kernel (default pager): [KERNEL]: no space in available paging segments
This message is repeated many times right up till crash.
My boot partition is 100GB and has 43G free. I have done nothing to alter SWAP size or location.
The server has been up in its current form for over a year. This problem first appeared about 3 months ago. I recently doubled my RAM from 2G to 4G to see if that would address this issue - the problem seemed to clear up for a while, but then returned. I've checked my disk integrity using disk utility - all seems well - and I'm getting no disk i/o errors.
Not hosting any mail services.
Services being hosted:
AFP, DHCP, DNS, iCal, OD, Print, Software Update, Web (wiki and calendaring).
I did have Server Admin running during the crash, and I also notice the following errors are repeated QUITE a lot in the log:
11/24/08 5:55:40 AM [0x0-0x1ad1ad].com.apple.ServerAdmin[19764] * ERROR: -[GRAxes computeLayout]:1124 - plotRect height = 0.000000 <= 0.0 *
11/24/08 5:55:40 AM [0x0-0x1ad1ad].com.apple.ServerAdmin[19764] * ERROR: -[GRChartView computeLayout]:1194 - Layout for overlay axes (0x172337c0) failed. *
Related?
Looking at /var/vm doesn't reveal much - pretty empty in there right now - but I suppose I'd have to be looking at it just before the server crashes (which would mean watching it all night - not too exciting).
I'm a bit of a newbie at command line troubleshooting. Can anyone give me an idea of how to troubleshoot this issue?
Many thanks!
Paul Westfall
Network Administrator
Breitenbush Hot Springs

Answer 1

Thanks for the ideas, Brian. I'll try that.
I do always have Server Admin open. The reason for this is that I've had to set up an Automator script to toggle Software Updtate service to start downloading from Apple at Midnight, then stop again at 3AM. And the reason for that is because our ISP is via Satellite, and bandwidth is severely restricted except between midnight and 3AM. I've tried to find or create some sort of script that would start and stop just the downloads - but all I've been able to figure out is a script that will start/stop ALL of software update service, which I do not want, since over night is prime time for clients to grab their updates from my server.
And now that I think of it - - I wonder if somehow Automator and/or SWUPD is creating the problem?
p