This week we will cover the Zend Cache, A script caching mechanism from Zend which will save pre-compiled versions of PHP scripts in order to avoid having to re-compile them every time, resulting in huge performance benefits. First we will go over the strengths and weaknesses of Zend's Cache and then we will move onto comparing the Zend Cache to other, open-source, free cache's.
When it comes to a product such as the Zend Cache its hard to measure an actual speedincrease the end user will receive, because it depends on the type of script is being run. When running an extremely long script (many lines of code), with little in the way of execution time (database transactions, socket access, etc.) than the Zend Cache can increase the performance of your script by tenfold. However, if you spend a lot of time in the execution phase, then the cache will still improve the speed of your scripts, but the increase will not be as signifigant.
Still, I ran some "un-official" tests on my laptop (PIII 733 MHz, 128mb ram, Linux, Apache, PHP, Zend Cache, MySQL), on a variety of scripts, some which would be taxingas far as execution time was concerned and not so heavy in regards to compile time, andsome which were taxing on compile time, but required very little in the way of execution time and then some which were a balance between the two. Overall, I foundout that the Zend Cache provided an average increase in the speed of my scripts of63.43%. Which I found to be a quite acceptable speed increase, considering that someof the scripts I tested were almost purely execution time. In fact I'd wager that onmost systems with larger scripts, you should be seeing something like a 100 - 200 %speed increase when using the Zend Cache (maybe more!)