Now let’s take a look at how efficient our controller can be in a web-server pattern:

This is a truly dramatic sight. The RAID 0 of 4 drives and RAID 10 array perform quite expectedly. The single hard disk drive and a RAID 0 array of 2 HDDs are much slower than they should be, while the performance of RAID 1 is almost normal.

The first thing that occurs to you is probably the fact that there has been some mistake made during the testing process. Let me deny that supposition completely right away. Our Intel IOMeter test script implies that all the subtests are performed one after another and the system is rebooted between the test sessions only. So, the WebServer pattern is performed within the same session with the FileServer pattern (first we run FileServer and then WebServer, without rebooting the system in-between).

So, if the controller goes through the FileServer with excellent results and then stumbles over the WebServer patterns, you shouldn’t blame the testers: the system or RAID settings do not get changed between the two pattern tests. All settings are adjusted BEFORE the script start running. And the complete testing cycle for the script with certain settings is about 14 hours non-stop (not taking into account the short breaks needed to reboot the system).

So, the reason for these abnormal performance results should probably lie in the controller drivers.

In our rating system built following the same rules as we have just described during our FileServer discussion the situation looks as follows:

RAID 0 array of 4 HDDs and RAID 10 array look very close to what we have just seen in FileServer pattern. The results demonstrated by other arrays are pretty confusing, I should say.