High CPU Usage

#1
Hello,

Quick bit of background, I volunteer with a youth group and since I'm the most tech savvy out of the bunch, I took on redesigning out website. With COVID-19, our entire program is running via the website so I created a Buddyboss/Wordpress website to accommodate our needs. It has been working out incredibly well.

Our program runs once per week. Unfortunately that means 200 people are signing into the website at the same time and the server seems to be struggling a bit at this time.

Server Specs
Type: VPS - Litespeed server
CPU: 8 (according to "Server Information" in WHM, Intel(R) Xeon(R) CPU E5-2690 0 @ 2.90GHz)
RAM: 16GB
Disk: 200GB SSD
Bandwidth: Unlimited

I am also using the asset cleanup plugin to remove css and js that are not being used from pages. I am using Cloudflare and the Litespeed cache plugin (which also includes serving images as .webp) and have Opcode Cache and Object Cache enabled.

When our 200 people are signing in at the same time, the server load shows between 7-10/8 cpus used. The most common processes used being admin-ajax.php. I know what script is causing this issue, but it is necessary for the website to function.

When looking at the real time stats, with PHP suEXEC Max Conn set to 10, the connections are maxed out at 10 and I get up to 25 in WaitQ. I understand this means I should increase the PHP suEXEC Max Conn. However in an experiment, I set PHP suEXEC Max Conn to 25 and while that lowered the WaitQ to essentially 0, my cpu load went to 27/8. Does that make sense?

Any suggestions would be appreciated. Thank you.
 

Pong

Administrator
Staff member
#2
Increasing "PHP suEXEC Max Conn" will increase the server load and it won't reduce the server load.

The key is "I know what script is causing this issue, but it is necessary for the website to function. " can the script be done at another way? Basically, you will need to reduce the php processes as much as you can.
 
#3
Thank you. I figured that would increase the server load, but I wanted to double check. Nothing I can do about the script sadly, it's part of the platform our website is using. I know they are working on it, but am just trying to do what I can in the meantime.

Thanks for your help!
 
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