Hi All,
Now I know there are lots of possible reasons for high load average on a server, and these have been discussed many time before, eg. (copied from another thread):
- A high server load can also be caused by a malicious script or a "runaway script" which can continously loop, dragging down the server's resources.
- Too many websites on the one server - with the cumulative resources resulting in high server load.
- Running out of memory and swapping to the swap file.
- Server backups or server updates are taking place.
- Misconfigured software causing errors.
- Users sending large mailing lists.
- Users trying to bounce spam.
- Users/spammers sending spam email.
- Hardware issues including memory leak, bad hard drive, and network card.
My request for help is this - please can some kind soul list some steps to take to attempt to methodically isolate the root cause of causes of the high load average.
Me, I'd start with the 'top' command. I'd check that the load average is indeed high. I'd check the %CPU and %MEM columns to see if a particular process was obviously hogging lots of one or both - and perhaps kill them if I was confident that it was safe to do so.
Whilst looking at 'top' I might also hit the letter 'c' on my keyboard to give more information in the COMMAND column about the command/process that is running.
I could also enter the command 'vmstat 1' to see if lots of swap memory is being used (si and so columns). I might consider adding more RAM if this were the case - but of course this might ease the problem, but not get to the root cause of the problem.
But let's say none of the above is giving me a strong indication of what's causing the high load. What techniques/tools/tests might I use?
Thanks v much.
Now I know there are lots of possible reasons for high load average on a server, and these have been discussed many time before, eg. (copied from another thread):
- A high server load can also be caused by a malicious script or a "runaway script" which can continously loop, dragging down the server's resources.
- Too many websites on the one server - with the cumulative resources resulting in high server load.
- Running out of memory and swapping to the swap file.
- Server backups or server updates are taking place.
- Misconfigured software causing errors.
- Users sending large mailing lists.
- Users trying to bounce spam.
- Users/spammers sending spam email.
- Hardware issues including memory leak, bad hard drive, and network card.
My request for help is this - please can some kind soul list some steps to take to attempt to methodically isolate the root cause of causes of the high load average.
Me, I'd start with the 'top' command. I'd check that the load average is indeed high. I'd check the %CPU and %MEM columns to see if a particular process was obviously hogging lots of one or both - and perhaps kill them if I was confident that it was safe to do so.
Whilst looking at 'top' I might also hit the letter 'c' on my keyboard to give more information in the COMMAND column about the command/process that is running.
I could also enter the command 'vmstat 1' to see if lots of swap memory is being used (si and so columns). I might consider adding more RAM if this were the case - but of course this might ease the problem, but not get to the root cause of the problem.
But let's say none of the above is giving me a strong indication of what's causing the high load. What techniques/tools/tests might I use?
Thanks v much.
