Topic: yet another performance question

Hello there all,

i have one page that uses periodically_call_remote to update about 65 divs on this page every 5 minutes or so. The page also uses a rather large background map.

the server we are using has 4 cpu at 2ghz, 8meg RAM and 5 disc RAID 5. our connection is 1.5 meg upload.

we seem to really get bogged down on high traffic times. I have watched gkrellm, and it doesn't seem to be the processors or RAM that is limiting anything.

Other php  sites hosted on the main server here (virtual hosts in apache) also slow down considerably.

i am using rails in production mode, fastcgi.

What kind of tool would you guys reccomend that i use to determine what my bottleneck is ?

could it be disc? i have tried to optimize my tables and indexes, but can't really tell what our limiting factor to speed things up here is.

Is ajax expensive on the server?

thanks for any tips.

Re: yet another performance question

AJAX can be expensive, depending on how it's used - if you make many small requests, each still needs to be processed and requires contextual overhead even if the actual processing of the request is fairly straight forward.

That said, it sounds like your problem may not be in raw request processing  - if that was the case you would presumably see a spike in CPU and RAM usage under load.

If it's not the processors or the RAM, it might be the database.

You can try running your queries outside of the site itself ... this will help determine. MySQL provides a lot of resources for MYSQL Optimisation.

If not the queries themselves, it may well be the disk, or perhaps a configuration setting in MySQL that it hard-limiting connections?

I have used MONyog - it's a MySQL Monitor and Advisor that looks at the internals of your MySQL configuration. I would install that and see if it points anything out.

Last edited by tobyhede (2007-06-11 21:13:13)

Toby Hede
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FiniteStateMachine - Software Development for Social Networks
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Re: yet another performance question

i am not seeing the cpu spike, suspiciously eying the disc, sql, and bandwidth. The main page has 72 div elements that update every 4 minutes with periodically_call_remote. I am trying to get them all wrapped in one element that will only need one update call to update all the divs.

thanks for the link, never heard of it before, will try it out in the morning.

thanks again