Hello, we are looking to switch to our own servers in a colo center. We are looking to get an Xserve for MySQL and an Xserve for website hosting. Each Xserve will be dual quad core Xeon 3.0 with 8gb RAM and 15K RPM Hard Drive. We will probably be handling 500,000 or more concurrent connections at certain times, and growing.
We had many issues with our dedicated hosting company so it is hard choose what hardware is needed.
Do we need multiple servers or could we run one? Or get two with lower or higher specs?
Anybody who runs a high traffic MySQL site or even website, if you could give you opinion on hardware needed that would be great.
Yeah, you'll actually start running into file descriptor limitations far before you get to 500k on one server. If you are really expecting 500k connections at a time, you will need a fleet of servers, my guess is you don't need anywhere close to that many at this point and time.
FreeBSD defaults to 12328 max file descriptors open at a time, thats system wide. I know OsX is loosly based on free, so it's default is probably somewhere around there too, you could look into increasing that number, but it's likely that apache and/or your database would start to choke under that kind of load, even with 8 cores and 8gb of ram.
I wouldn't worry about it until you actually start running into issues, I think you'd be surprised on just how many 500k concurrent really is. When you start running into issues, make a database machine and a few apache head boxes and that'll scale you up pretty nicely for awhile. If you need more database machines, then start looking into some database replication solutions, depending on your application.