Forgive me if this takes a while to read, but I wanted to provide as much up front information as possible to prevent a lot of back and forth and wasting of your time. So thank you in advance!
We have recently upgraded from 1.9 to 2.4.3 via our former support company who is no longer supporting us (and apparently didn't really support us originally with everything we are uncovering).
Since the upgrade, we have had major performance issues which originally required an upgrade of RAM, processors, and other hardware resources. We have APC running and caching properly so the site flies when it is running properly. We also discovered that the cron was not run on our system for over 3 years so after nearly 8 hours of running that script, our database shrunk considerably and the performance increased dramatically as well.
We have over 36,000 users, 1900 courses and have typically 2,000-3,000 users online at most times of the day. Now the issues...
During peak times of the day as well as heavy quiz usage, we are experiencing a number of Database Connection Failed issues. I have read and read about potential fixes, but I can't seem to crack the final settings for our system.
Basically I am in search of guidance on number of connections, user connections, etc. that I need for this to run properly and keep our teachers from being so frustrated because I don't blame them a bit right now.
Provided resources (hardware wise) was not an issue, what would be a solid, stable setup to properly support the performance that we require. Again heavy quiz usage.
Also if you have an idea of something to try to help performance that I probably don't know, please feel free to chime in. I am willing to listen and learn.
Thank you again!