Web Hosting Talk : Web Hosting Main Forums : Dedicated Server : MySQL via iSCSI Architecture Question

[drewnick]

I don't know if this is the correct place to post this, but it involves a dedicated server.

We are having our databases get hit pretty hard, and on our HP G2 server with U320 discs, performance is taking a hit.

Our datacenter offers iSCSI space on a high performance SAN with the intention of offering optimized i/o for SQL transactions. If I mount this iSCSI drive via gigabit ethernet, should performance increase?

It's just hard for me to get in my head that a disc on the other side of the building will be faster than the disc in the server. Thus, I am here looking for opinions.

[Krazy]

this is G2 machine, check if the cpu is bottleneck, then look for how much disk transfers/sec (disk IO) happening on the mysql disk drive.
U320 should not be having a problem.

[sprintserve]

What exactly is your bottleneck? That would be your critical question. A lot of times, it could be badly indexed database, or inefficient queries etc. Or perhaps you are simply not having enough CPU cycles etc.

How many concurrent queries are you talking about? What about the database size and the nature of data / queries?

You also will need to be specific on your exact current disk configuration, the raid setup if any, the theoretical I/O bandwidth available, and get some details from your datacenter on their SAN setup and do a comparison.

In short, it's too many variables to give a black and white answer. You need to provide some additional information.

[Lightwave]

Uhm, what model HP G2 rev server are you talking about? Unless it's one of the newest models... I'm guessing you're talking about something fairly ancient. (I mean, I have a dozen HP DL360 G3s under my bed that I can't sell for $50/ea).

So, while a good iSCSI array and interconnect would likely show significant performance benefits... your underlying hardware could cause more problems than it's worth. Most good iSCSI SANS that have benchmarked MySQL performance have done so using FiberChannel which was likely a good bit faster than a single GigE, but perhaps not.

[funkywizard]

A couple 80gb intel x-25m's in raid 1, or, for even faster performance, 32gb intel x-25e's in raid 1, would blow away whatever SAN they're thinking of putting you on, and will likely be cheaper as well.

Everyone else here is right though, you should find out if i/o is your bottleneck before switching out to something else. Maybe cpu is your limiting factor, or ram, or your queries are not optimized, or your database is not indexed. But definitely if i/o is your problem, an intel SSD will take care of that immediately.

[drewnick]

thanks for the replies. I'll check and see if it's I/O causing a problem. Good call.