New Thread on Board Performance

[Giraffe]

@TubaDiva

I’ll ask Jerry. I’m pretty sure we got two servers, though.

You do:

@jdavis

Finally, waiting in the wings is a new front end web server to replace what is currently being used. Right now the front end server is on 3 year old hardware. The new server is a current operating system build and new software stack that should provide performance benefits to what we see today. Testing is ongoing. It will be installed sometime in the next few weeks. As for the back end database we believe it has more than enough horsepower. The SDMB database shares resources on a 64 core 5 server database cluster running with SSD storage technology. The SDMB database usage averages about 4 cores of utilization under normal load and can peak up to 11 cores so there is of headroom on the back end.

(bolding mine)

Your database is hosted on a cluster of five servers, so if one of them is doing something weird that could explain the randomness of the problem.

I’ll also ask him if they’re synced. They’re at DesertNet, so it’s not like Jerry can walk into the server room and look at stuff directly.

This would be a software sync (i.e. running a program that keeps the computer’s clock synced with a standard time, e.g. NIST), not anything to do with the physical hardware. So as long as he can remotely log into each server, he can just check the system time and make sure they’re the same. (I’d be very very surprised if they aren’t, that’s pretty standard, but different computers disagreeing about what time it is could explain Siam Sam’s problem.) This also might be something he just wants to call to DesertNet’s attention, since the database cluster is a shared resource: maybe they can do some standard diagnostics to make sure each server in the cluster is working properly and able to handle mySQL queries?

But here’s the thing: If it’s a system-wide situation why is it only affecting a few people? Why just SiamSam and a couple other people? Not trying to be difficult here, just saying.

It’s a very good question. The root cause may be a random but unlikely occurrence, e.g. the problem only happens when your last logout was processed by database server #3 and your login is processed by database server #5. Some users may be doing something to trigger this event more often. For instance, I personally suspect the fact that Siam Sam is constantly logging out and logging back in has something to do with it – most users just leave themselves logged in on whatever computer(s) they use. If the problem occurs most often during login, only a small fraction of posters will even have a chance to see it. Add in the fact that posters who don’t use the New Posts feature could be hit by it and don’t notice or care, and your pool of people who are hit by this shrinks down to a handful.