On one of my hosting I am sometimes getting error that generates 503 response.
[notice] [client mod_overload: Overloaded, 1 minute load average, current load: 101, max load allowed: 90
I have tried to google it but there is not much information about this error nor about mod_overload itself.
My guess is that this mod sends 503 code if the is more than allowed number of request at one time.
Could someone confirm if I am right or not and if not what does it do.
PS: I have send email to hosting company for explanation but would like to get answer from independent sources as well.
Apache module which is checking load average and when it is higher then defined stops current request(has ability to stop other request too). Since 0.2 settings can be set per directory/virtualhost/location.
For me this one paragraph doesn't give much of explanation about how this mod works or to be more precise how it calculates load average. Which variables does it takes into account is it only CPU and memory usage, maybe number of parallel request? How big influence may have a website's code?
The website I have this problem with was not developed by me but I just got to modify it and find source of this error. It has some poor quality code, there was lots of PHP warnings at each request that were always written to log files. Could it be a reason of increased load?