Getting Optimal Performance from Your Server

A typical script will take about one second of CPU time to run a session that lasts about five minutes. You might extrapolate from this that your server can handle an even load of about 300 simultaneous users.

(5 minutes/session) * (60 seconds/minute) / (1 second/session)

In reality, the server can handle less than this because memory will become a problem before you reach CPU speed limits.

A typical session requires about 1.2 MB of RAM to run. If your server has 128MB and the operating system requires 32MB, then you have about 96MB left to hold active sessions. This means your server can handle about 80 sessions before virtual memory is required.

96MB/(1.2MB/session)

Your server will be able to handle more than 80 sessions, but performance will degrade because your computer will spend most of its time swapping sessions into and out of virtual memory space on your hard disk.

The bottom line on performance is that a fast processor will make sessions start quickly and provide snappy responses; but memory capacity will limit performance under heavy loading. There are several server options you can set to help maximize the amount of memory available for new sessions. Each is described below.

See Also

Maximum Simultaneous Sessions Setting

Load Sharing

Kill Orphans with Cookies

Session Timeout