I have my webhosting with a premium plan ($60 a month) with a company that offers Clustered Server Technology for its "Enterprise" level plan.
The theory (they say) is that multiple servers sharing and running multiple sites is better than a Virtual Private Network (VPN) that runs on one server. Load is shifted between servers as needed, and if one server is down, your site doesn't go down. Separate servers handling e-mail and the mySQL database ease the load from the http servers.
I run 4 sites and two of them have a WordPress blog, a bbPress Forum, and other PHP scripts that access their mySQL databases. WordPress and bbPress have already been optimized and all the hints and tips for speeding up those systems have already been applied, including using a WordPress cache plugin and minimizing the number of mySQL calls.
The sites are very fast for standard HTML and PHP pages. But there is some sort of delay with the WordPress and bbPages despite their optimization. I've done timings with tools such as YSlow, and the page is generated fast enough (in under a second) once it gets around to doing it. But there can be a 2 to 8 second delay, when the browser simply says "Opening page..." before the page generation seems to begin.
I have been unable over several months to track down what might be causing this "delay" before the page begins generating. Any ideas that might help me solve this will be much appreciated.
