Sorry to piggy-back on Basil's thread, but I seem to have similar issues. My web host enabled the slow queries log and came up with the following:

They said but I don't understand what the log entry is telling me. I had some "overhead" so optimized my tables, but not sure what else I can do...

Rick should look at this. You've got a pretty high number of posts but geez. If I'm reading this right it's counting how many posts are in ubbt_POSTS and and how many topics are in ubbt_TOPICS for forum 14 that are approved and have been posted since 1203364960.

Shouldn't be a big deal. It's only 91k rows. It's scanning all of them though, but still it's only 91k rows.

"Only" 91,000 rows... Why is this query even happening??

Forum #14 happens to be my (dreaded!) "Word Games" forum where idiots post nonsense over and over to build their post counts (hence I cannot wait for 7.3 so all that doesn't count any more!)...

And most importantly... could this be causing the server lag I've been experiencing?

It's not just Forum 14... and it gets worse...

Let me guess. You have the "Show total # of unread posts per forum?" checked under Forum Summary Options. Where right under it, it says:

Warning: This can cause excess load and contribute to slow speed.



Basically, if someone never reads a forum, every time they visit it has to figure out how many unread posts are in each forum. As the number of topics and posts grow, the number of rows that are scanned grows.

If all of your users regularly visit each forum, the queries are pretty quick. But if they only visit a few of the forums, the number of unread posts in the other forums grow, leading to larger query times.

One of the main reasons you don't see this feature on many other forums, is there is no non-resource intensive way to do it. We kept it in as an option because some people love it, but it's a resource hog, plain and simple

Forum Display Options has another one of these features with the same warning.

Yes, I do have that enabled. But does it make sense that normally I'll see something like "Generated in 0.01 seconds in which 0 seconds were spent on a total of 22 queries" but just periodically (some good days, some bad days) it'd take 10-20-30 or even close to a minute to load the page?

And if I wanted to test this, is there a way to "Mark All Read" for every member, and/or, if I uncheck the box will it clear all that info out of the database?

Thanks,

JG

Yes, you could have an influx of users at those times that work a certain shift that come in at the period your forums choke that rarely visit certain forums...

Well, I disabled both about 26 hours ago and {knock on wood} haven't had a single lag issue since, so thanks! ...but some of my members are bitching about it being gone. I may try one or the other and see how that works out as a compromise. But in any event - that seems to have made a big difference, so thanks!