[Forum] CPU Usage Spikes from Recurring Processes

[mbecker]

I've noticed a spike in CPU usage every 6 hours into the 60-80% range for 30-45 minutes. I've contacted my hosting provider and they've identified it as being related to vBulletin but that's as far as they're able to determine.

The spikes don't correspond with any Scheduled Tasks in CPanel.

I didn't see this happening before I recently upgraded to vBulletin 4.1.8

What sort of things can I look into to fix this or at least determine what's going on?

I'm running this on a dedicated IIS server (Windows 2003) and not Apache.

I see a similar post but on vBulletin 3.8: https://www.vbulletin.com/forum/show...ization-spikes

[Mr.Tampax]

Turn on logging of "slow queries", maybe it's any cleaning task forum (you can see this list in admintCP).

[mbecker]

Forgive the dumb question, but how do I do that? I'm searching the forums for instructions but can't find anything so far.

[Mr.Tampax]

You should be included in "my.ini" these options:


log-slow-queries = path_to_logs_dir
long_query_time = 30


and restart mysql.


In the logs you can find all the requests, lasting more than 30 seconds, and then by searching through files to find out exactly what script calls them.


You can also try to disable all clearing task in adminCP, and wait a day. If CPU will not overloaded - turn on task one by one ("start now"), watching CPU usage.

[mbecker]

Turns out it was a large amount of traffic from a specific group of IP addresses, possibly as advertising click spam. IPs are blocked and now things appear to be back to normal.