Poor RAID0 performance, need some help

[Ksu]

Hi there,

I'm fairly new to RAID systems so sorry if this has been discussed many times, I've read so many different opinions that I'm now really confused. I need some opinions on my setup.

I did some benchmarking and the performance looks pretty poor. My RAID0 consists of 3 x 250 GB Samsung SP2504C, 7200 on the Intel RAID Controller of the ASUS P5B Deluxe.

I'm doing mainly video editing, also playing some new games every now and then and also using smaller files like MP3s. I heard for large files a larger Stripe Size gains better performance, so because of that I took a 128kb stripe size. Lots of people say 16kb has the best performance, but also with larger files?
Yesterday I read something about the NTFS cluster size also influencing performance. Didn't know that before so I have the default cluster size of 4kb. From what I have heard thats bad, but then again everyone has a different opinion, some say cluster size should be equal to the stripe size, others say it shoild be 1/4 of the stripe size.

So, what settings should I use for handling large files, smaller Files like MP3s and gaming? with the best possible performance? I don't care much about CPU usage, I have an E6400@3.2GHz so it should do well.

Here are my results with HDTune and HDTach:

HDTune:
51266

HDTach 8 MB Test:
51264

HDTach 32 MB Test:
51265


Is my observation correct that this is poor performance?

Another thing: Is it possible to make a backup of my system partition with the above stripe/cluster size and then restoring it back on a partition with different stripe/cluster size? If so, which program works well? I think Acronis True Image has a 14 day trial so that should do it.

Sorry again if this has been discussed many times. I just don't get it :confused:

TIA

[Grinch]

your graphs look like that due to a high stripe size...if you want it to look more linear than go with 16K stripe...as far as changing the cluster size there is a very easy way to do so:

The "EASIEST" way to change your cluster size is to have a 3rd drive with Win XP on it....here is what you need to do.

1. Have 3rd drive with Win XP
2. Go to bios and change boot order to 3rd drive b4 Raid
3. Once in windows goto "Disk Management" (as soon as you click on it you will have a window pop up and ask you to select drive and it will also want to know if you want to convert drive to a dynamic disk...I always choose no)

4. You will see your raid drives as 1 BIG drive..now all you do is right click on the drive and click partion...primary partition...set size...now is where you can choose cluster size...you will have 3 boxes to check off...

5. NTFS or FAT32...Volume Label....Cluster Size......
6. After you check all of that off then you click off quick format and Voila...you have done it now do same on rest of drives....

7. once you have setup all your partitons and selected cluster sizes...shutdown PC unplug 3rd drive...change boot order so CD rom will be a bootable device b4 raid device and you are good to go on a clean install....remember once you get into the window when setting up XP you have choices to format drives again and choose where XP get sinstalled ...choose to leave as is...no need to format again cuz it will default to 4k cluster again.....



let me know how this goes for ....I have been doing this trick now for a LONG time and I know for a fact that this is a fast and easy way...without using any 3rd party software.....

[Ksu]

Thanks for the tip! I'll try that. But if it would be possible somehow, I would rather like to backup up my sys partition. I have configured my OS as I need it and installed all programs I need. Doing it again would be a pain in the a**, but oh well, if I can't backup my sys partition then I'll just reformat like you described.

If I use 16k stripes, will my results just get more linear or will my average transfer rate also increase? Especially looking at the HDTune result, it looks like there is something wrong with my RAID. Still can't figure out if it's because of my stripe size...

Heres a result with a single Samsung 2504C (from HDTune website):

http://hdtune.com/results/Samsung_SP2504C%285%29.gif

Comparing with my result, I get disappointed :(
HDTune doesn't bench the filesystem, is that correct? So it can't be the cluster size for now. Either it has to do with the stripe size or my overclocked FSB?!? FSB is at 400 right now. When I get home I'll do some tests.

[Grinch]

For your graphs and benchmarks to be higher like this:

http://s2.supload.com/thumbs/default/raidraptors-20060914165519.jpg (http://s2.supload.com/free/raidraptors-20060914165519.jpg/view/)


Then you will have to break raid array and rebuild using 16K Stripe...and use the 3rd drive method for 16K cluster...but in all honesty the default 4K cluster is fine as well....:woot: :toast: :clap:


also look at these links:
http://www.xtremesystems.org/forums/showthread.php?t=98643&page=3
http://www.xtremesystems.org/forums/showpost.php?p=1467294&postcount=183
http://www.xtremesystems.org/forums/showpost.php?p=1436670&postcount=53