Raid 10 Array Inconsistent Results

[Snaggletooth]

I have really inconsistent results. I am running 4 WDC WD2500BEKT in a software raid that is integrated in my motherboard (MSI 785GM-E65).

I spent the day running numerous tests all with different results for no rhyme or reason.

The ranges were:

Disk Mark Totals: 295.9 to 609.4
Disk Sequential Read: 52.1 to 146.2
Disk Sequential Write: 14.5 to 26.5
Disk Random Read + Write: 2.75 to 5.1

Anyone know why? Any suggestions?

Thanks in advance!

[David (PassMark)]

Could be background activity on the drive, fragmentation, different positioning of the test file across the drives, differences in the state of the various caches when the test was run, etc..

If it is software RAID, then it won't be integrated in the motherboard.

[Snaggletooth]

Still no luck

I appreciate the prompt reply.

I killed all the background processes I could and file fragmentation is less than 1%.

4 different tests indicate that those huge range variables still apply.

What I meant by software raid, was to specify that I was not using an add in card with it's own hardware resources.

Any other advice on things to try?

[David (PassMark)]

It could be that the performance of the RAID set really does vary.

Doing a cold reboot each time and running the disk test just one time, once the machine is idle, should produce a more consistent cache situation.

Also using the advanced disk test to select much larger test files (e.g. 20GB+) will also remove the caching effects.

Software RAID doesn't us any hardware. In Windows it is also called "dynamic disks".
http://support.microsoft.com/kb/816307

When you say RAID 10 I am guessing you are talking about RAID 0+1.