Jun 10 2008
Apache Performance Tunning
“Premature optimization is the root of all evil.” — Donald Knuth.
…in other words, don’t implement in extra complexity if you don’t need it. A site handling a few thousand requests per day will do fine on a default configuration and just about any hardware. This article is geared towards a site that needs to handle multiple concurrent requests [ten to several hundred per second].
General [in order of importance]
RAM
The single biggest issue affecting webserver performance is RAM. Have as much RAM as your hardware, OS, and funds allow [within reason].
The more RAM your system has, the more processes [and threads] Apache can allocate and use; which directly translates into the amount of concurrent requests/clients Apache can serve.
Generally speaking, disk I/O is usually a close 2nd, followed by CPU speed and network link. Note that a single PII 400 Mhz with 128-256 Megs of RAM can saturate a T3 (45 Mbps) line.