My website gets stuck for few seconds, before starting to work again

#1
I am running a website on OpenLiteSpeed Server with Digital Ocean.
The configuration of my droplet is:

4 GB Memory
80 GB Disk
OpenLiteSpeed WordPress 5.6 on Ubuntu 20.04

Sometime my website takes a long 3-4 seconds to respond to a request. Recently this has become very common and it is occurring very frequently.
To investigate the issue, I checked Logs to find the following.

From stderr.log

Code:
2021-01-14 05:29:49.994 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.094 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.194 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.294 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.395 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.495 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.595 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.695 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.795 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.896 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:50.996 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.096 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.196 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.296 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.396 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.496 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.597 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.697 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.797 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.897 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.997 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.097 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.197 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.298 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.398 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.498 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.598 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.698 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.

From error.log

Code:
2021-01-14 06:03:50.037986 [NOTICE] [111.11.111.!:52950-Q:71B8448DC86D8853-9#wordpress] No request delivery notification has been received from LSAPI application, possible dead lock.
2021-01-14 06:03:50.038014 [NOTICE] [111.11.111.1:60056#wordpress] No request delivery notification has been received from LSAPI application, possible dead lock.
2021-01-14 06:03:50.038034 [NOTICE] [111.11.111.1.109:45606-Q:2707992EDC0AB4D1-117#wordpress] No request delivery notification has been received from LSAPI application, possible dead lock.
2021-01-14 06:03:54.031122 [NOTICE] [111.11.111.1.109:45606-Q:2707992EDC0AB4D1-121#wordpress] No request delivery notification has been received from LSAPI application, possible dead lock.
There are lots of logs like this. (Changed the IP value)

Every other configuration on the instance is default except, memory_limit = 512M.

Does these logs tell anything about why my website is getting stuck ?
 

Cold-Egg

Administrator
#2
Hi,
According to the error log "Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN." that your server has hit the limit, please go to WebAdmin console > Server Configuration > External App > lSPHP7x, update both Max Connections and LSAPI_CHILDREN from 10 to a higher number, e.g. 30. Let us know if it works.
 
#4
Hey @Cold-Egg I said as you asked but I still see the same errors.

Code:
2021-01-14 05:29:51.797 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.897 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:51.997 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.097 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.197 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.298 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.398 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.498 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.598 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.
2021-01-14 05:29:52.698 [STDERR] [171231] Reached max children process limit: 10, extra: 0, current: 10, busy: 10, please increase LSAPI_CHILDREN.

I have attached the changes you suggested and did a graceful restart. It still doesn't reflect in my error.

Am I doing something wrong ? Screenshot 2021-01-14 170538.png
 
#6
Hey @Cold-Egg, I was able to get it work. The issue has been resolved.

I do have some question around it though.

What exactly are those that I changed ? And does one come up with a number. Like 30 ? Is there any resource around this that I can read or any formula which would determine this.

Thanks!
 
Top