IO load takes IO wait into it's calculation, so it may be a writer process hammering the disks which are under powered for the IO load.
Run an iostat under these situations to find the disks causing the high waits.
-Ross
-----Original Message----- From: centos-bounces@centos.org centos-bounces@centos.org To: CentOS mailing list centos@centos.org Sent: Wed Dec 05 09:39:41 2007 Subject: [CentOS] weird load values
Hi List,
I'm stumped by this:
load average: 10.65, 594.71, 526.58
We're monitoring load every ~3 minutes. It'll be fine (i.e. something like load average: 2.14, 1.27, 1.03), and then in a single sample, jump to something like the above. This seems to happen once a week or so on a few different servers (all running in a similar application). I've never seen the 1 minute sample spike as high as the 5 or 15 minute samples.
Seeing as that last value is a 15 minute period, well, it doesn't seem possible that one can have a 500+ 15 minute sample without having observed a spike in the 5 minute sample at least 5 minutes before.
Also, there aren't 500+ processes on these systems -- it's typically around 100 total processes (ps auxw | wc -l). (Is there a way to see the total count of kernel-level threads?)
Thoughts?
best, Jeff
Linux someHostName 2.6.18-8.1.8.el5 #1 SMP Tue Jul 10 06:39:17 EDT 2007 x86_64 x86_64 x86_64 GNU/Linux
CentOS release 5 (Final)
09:31:15 up 65 days, 17:45, 2 users, load average: 0.92, 200.91, 371.30
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