100% disk I/O usage

I’m not really sure what causes the problem.
I think it first appeared after the latest upgrade on 1.7.3.
Sometimes (it just happens occasionally every 2 or 3 days) my Azure VM shows me huge disk writing. The VM is almost inaccessible even through putty. The websites just show 503.

I googled that a bit and installed fatrace to track what’s happening.
So this is a small excerpt from what I get from fatrace


lsphp(29720): W /tmp/phppfC9bR
lsphp(29720): W /tmp/phppfC9bR
lsphp(29720): W /tmp/phppfC9bR
lsphp(29720): W /tmp/phppfC9bR
lsphp(29724): W /tmp/phpWmcw7R
lsphp(29724): W /tmp/phpWmcw7R
lsphp(29724): W /tmp/phpWmcw7R
lsphp(29724): W /tmp/phpWmcw7R
lsphp(29724): W /tmp/phpWmcw7R
lsphp(29724): W /tmp/phpWmcw7R
lsphp(29724): W /tmp/phpWmcw7R
lscpd(592): W /usr/local/lscp/logs/error.log
lscpd(591): W /usr/local/lscp/logs/error.log
lsphp(29720): W /tmp/phppfC9bR
lsphp(29720): W /tmp/phppfC9bR
lsphp(29720): W /tmp/phppfC9bR
lsphp(29720): W /tmp/phppfC9bR
lsphp(29720): W /tmp/phppfC9bR
lsphp(29720): W /tmp/phppfC9bR
lsphp(29724): W /tmp/phpWmcw7R
lsphp(29724): W /tmp/phpWmcw7R

This continues really long. But sometimes it resolves after a while and the VM continues as nothing ever happended.
When I see it happen, I usually restart the VM and the problem is solved for the next days.

So what is the problem? And how to fix it?
Any help and hints are appreciated :wink:

Thanks Alex

Do you see anything in LiteSpeed error logs?

I got to cyberpanel dashboard->logs->error logs. There’s only this right now:
2018-10-31 10:12:02.511528 [NOTICE] [23.97.188.64:44706] [STDERR] PHP Warning: strpos(): Empty needle in /home/XYZ.com/public_html/wp-content/plugins/ginger/front/gingerfront.core.php on line 250
(That’s a cookie consent plugin)

But I only see the last 50 entries, which are all the same and from the last 2 minutes or so. (The VM works without problems right now.) Do I see more if I follow this way? How to turn on Extensive Debug logs in OpenLiteSpeed! — CyberPanel - WebHosting Control Panel for OpenLiteSpeed

Yup, you can turn on debug log and if you run into the same issue you can open a support ticket at https://store.litespeedtech.com/store/contact.php

CyberPanel upgrade also upgrades OpenLiteSpeed, which might have caused the issue.