How to trace what cause of server high load in the past

_mz · 07-29-2013, 03:19 AM

Hi guys,

If your server's load was high from 2AM - 4AM while you were sleeping, you would have missed what took place. While sar can be helpful to show you what specific resources were high during that time, it won't tell you the cause of the high usage. How can we trace what was happened in the past that caused server high load?

Mr. Bill · 07-29-2013, 04:19 AM

When troubleshooting any issue with a Linux server, the most useful resources at one's disposal are the log files. They can all be found in the /var/log directory.

Habitual · 07-29-2013, 02:58 PM

http://collectl.sourceforge.net/ easily can do this.

Edit: It will not tell you what happened in the past.
You'll have to run it in collection mode during a spike in resource usage, and then play it back.

syg00 · 07-29-2013, 03:01 PM

If you don't have the data, you don't have a chance. Wild guess would be check cron for updatedb.

_mz · 07-30-2013, 02:24 AM

Quote:

Originally Posted by Mr. Bill

When troubleshooting any issue with a Linux server, the most useful resources at one's disposal are the log files. They can all be found in the /var/log directory.

The thing is there are no suspicious errors in any system logs