I was having my students register on a site today. They were to register, send me a conversation so that I could assign them to the "student" user group. After the first 10 or so students registered, several found out that they could send "conversations" to each other. Two students in particular kept sending messages. As this happened - loading pages became a crawl. Other students were paused to send messages. The site started tossing random errors when kids would try to load a page. As soon as the two kids stopped sending their conversations then the site went back to loading fine.
This particular site I'm describing, btw, is generally very fast.
What tweaks should be done to allow multiple conversations to happen without slowing down the site?
This is a true story. It happened Monday in the school computer lab. I was at the teacher's computer and physically watching the two kids - who were across the room from each other while 43 other kids in the room were also trying to register or waiting for my reply to their conversation that they had proper permissions.*
We will be in the lab again today but I'm not sure I'll be able to run the top command because the school network is filtered and monitored.
* Yes - there are 45 high school kids enrolled in my class that period.
For some problems I can come up with guesses and solutions based on observation. But I see no reason for this problem so I first want to confirm that it's happening. It could have been coincidence or a temporary problem.
Period 5 (9th graders, do not use conversations): 36 students. No slowdown.
Period 6 (10th graders, using conversations): 45 kids. Massive slowdown. Pages would not load in XF. I could easily load WP blogs. Looks like if I tried to post reply in an XF conversation at the same time an alert was coming in then the error would be shown.
No conversation essential add-on is installed.
I appreciate everyone's input.
These are the phpinfo() values that might be useful.