How to tell where the bottleneck is at?

About 3 weeks ago my dedicated server was upgraded to a quad core Intel with 8 gigs of memory. On that server I'am running 3 vbulletin forum, and about 5 wordpress blogs.

Out of all of those sites, only one gets any real traffic.

As long as the main site has around 300- 500 people on it at a time, everything is fine. Once we get 600+, and especially 700 people on the site, it starts slowing down to 5+ second response times.

How do I go about trouble shooting where the bottle neck is at?

Here are some system stats:

Server Type: Linux
Web Server: Apache v2.0.63 (cgi)
PHP: 5.2.11
PHP Max Post Size: 16.00 MB
PHP Maximum Upload Size: 100.00 MB
PHP Memory Limit: 128.00 MB
MySQL Version: 5.0.89-community
MySQL Packet Size: 64.00 MB

 

I know little about this, but first thing I would do is get rid of Apache and install nigix...
It runs so much faster...

 

Kevin, have you considered making the switch over to LiteSpeed? I run this on a couple of my machines and could not be happier with the performance (in comparison to Apache). These machines both run at least 8GB of DDR3 RAM and are Core i7 powered. I was skeptical at first, but LS is much more performance-oriented.

Not to mention, it cut down the number of unnecessary processes by about 45%, sometimes even more (depending on the situation).

 

Will vbulletin run on nigix?

I did a quick google search and did not find anything. Wikipedia said that wordpress.com is using nigix, and that it is the only web server that can handle 8,000 request per second.

No, I have not considered it. But I need to do something to improve performance.

 

If it's a viable option, I'd consider looking into it.

The conversion (or install) process took me all of 30 minutes to finish, and there was only a brief period of slowness (along with a very miniscule amount of downtime) after completion. If your server runs cPanel/WHM, LiteSpeed can be managed entirely via WHM's interface and can also be disabled with one click of the mouse. In other words, you can switch between Apache and LiteSpeed when necessary, or if desired. I've never found the need to do so, but it's nice to have that option nevertheless.

 

I've been reading up on how to speed things up.

Here is an extremely simple thread you could read.
vBulletin Community Forum

My thought was to go with nginx and apache. But Chris makes it sound so easy I may look into litespeed.

"TECK" started this thread about nginx (engine x) and thought it was much better that litespeed, but that was started December 2007, so litespeed may have improved
vBulletin Community Forum

And there is 'noatime' that can be turned off.
vBulletin Community Forum!


If it were me, I would experiment on a spare hosting account, cheap vps.

 

Thank you Abomination for that link, it explained a lot.

A properly configured apache server should be able to handle my server load with no problem. Does anyone have a good example of an apache server config?

How do I check how much memory apache is using, and now much memory apache needs?

 

I am that last person that should give technical advice, so I won't.


Have you read the server configuration forums at vb?
vBulletin Community Forum

Did you ask George over there? He posts suggested server configurations in most threads there.



My apologies in advance. The links posted are only accessible for vb licensed customers.

 

The answer is yes...vB runs fine off of it.
run nigix on a seperate port while you test it and you will save yourself any downtime