Moodle/Apache Disk Usage Performance Hit

[_techie_]

Hi,

We have been running Moodle successfully for the past couple of months with good usage from students and staff.

We are running it on debian, with apache, php, and mysql, all on one box, which is virtualised on esxi 3.5.

In the past week, we have noticed that the server which Moodle sits on, is occasionally using very high disk usage, which slows moodle down, so that it cannot even deliver requests for web pages. The CPU, memory, and network usage also drop down to a minimum, rather than the normal use levels.

Does anyone know what might cause this problem. My colleague believes it might be something to do with a cron.php script running, or some sort of backup running in the background?

Any help would be appreciated, as we are scratching our heads on this one. I don't think it is any form of DoS attack, as the network usage is basically nothing.

HELP!

Thanks,
techie

[Butters]

Have you set manual coursebackups? These are triggered by Cron Script and could be running at the specified time.

[_techie_]

Thanks,

It was set to run today (Tuesday), Thursday and Saturday at 2:0 From the logs on vmware client, it appears that this was running correctly on the Saturday, but not today?? It started today at 09:05am right at unit 1!!!!

Is there a problem with cron wiping out our clock settings?

Thanks,

[_techie_]

Hi,
Returning to this thread a few days on, and we have been monitoring it closely with vmware client.
It appears that the disk usage is not very high, but being sustained over a period of about 20 minutes or so. During this time, the esx grants more memory to our debian/moodle box, the CPU usage drops to 'almost' nothing, and the network activitiy drops to zero. I guess the lack of network connection is why apache cannot deliver webpages out to workstations around school, but as to what is causing it, is a mystery at present. Any other ideas? as we switched off backups for except for saturday only, (in moodle), so it can't be that.

Thanks,