MyBB Community Forums

Does anyone know how many PMs MyBB can handle before it starts to be too many?

I have MyBB running, and it was doing fine until sometime last year. Around then, the PM section started being slow to load (could take up to half a minute, while forum threads would load instantly). Sending a PM could take several minutes. A few days ago, the problem became worse where a few people sending PMs causes the Apache2 daemon (httpd) to crash due to being out of memory. (The server has 512 MB of RAM available to it.)

I cloned the forums (copied the database, copied the MyBB installation), and in that test environment, I deleted all PMs from before January 1st, 2012 (which was 168,501 PMs). After that, the test environment copy of MyBB would load the PM section instantly, and would send PMs instantly.

I'm wondering, is there a limit where MyBB simply cannot handle PMs? The forum I run has 14,253 threads containing 123,313 posts, and there are no problems there.

At this point I don't know where the cause of the slowdowns is, so it might not even be in MyBB. Since pruning the PMs seems to work as a solution (at least in testing; haven't tried it on the actual forums yet as I want to ensure I have a usable back-up for just the PMs before I trim them), I was curious: does anyone else have MyBB running with over 170,000 PMs, and have no issues with speed when sending PMs?

For the record, I'm currently running MyBB Version 1.6.4 (haven't yet upgraded to 1.6.5 due to trying to figure out the private messaging/httpd dying issue).

Update: I cleared out older PMs, and now the PM system is super-fast. I'm still getting the server running out of memory and closing Apache, so clearly that was unrelated to the slow PM system. Back to the drawing board for me on figuring the memory hog!

You can get access to the Big Board Owners section of MyBB and get lots of tips about how to run a large board by going here: http://community.mybb.com/usercp.php?action=usergroups

I recall labrocca was talking about PM's on HF once but I can't seem to find the thread....

Thanks for the suggesting on asking at the Big Board Owners section. I'll definitely look into that right away.

I know for sure it can handle much much more.

Thanks for the confirmation, Solidus. I figured MyBB could handle a large number of PMs in the database. I'm back to wondering what exactly the cause of the problem for my forum is, but at least my testing did show what seems like it will be a resolution (clearing out older PMs) for whatever the issue may be.

How many active users are on at any time? 512mb ram is not much, I used more than that when I had that many posts.
Coming into big board group also as Paul said, there are many tips for mysql tuning, lowering memory footprint and such.

I'm not certain what the number of users is at the higher points of a day, but it's probably somewhere between 25 and 50 at one time. Kind of hard to tell since I have this current issue (not related to MyBB) where I get a ton of Apache processes that eat up all the server's memory and shuts down Apache, making it hard to see how many people are on the forums... (I think I may have also had my request to join the big board groups rejected as my server went down right after I went to bed last night, and today the big board groups has "Join Group" rather than the message saying I requested to join Saturday. Oops.)

The 512 MB of RAM hasn't been an issue historically. I'm probably going to try nginx (which I've used elsewhere before and really like) and see if that helps. But this is getting really off topic, and away from MyBB discussion. If I can eventually get into the big board groups, I'll definitely be reading through olders messages there to see if there's anything I can improve in my site's own setup!

I've also used nginx with my MyBB forum, it helps greatly. There is discussion on this in the big board section.