Windows RAID Problem

[flounder43]

I have a Gigabyte 7VRXP that has a Promise RAID onboard. I installed two identical ATA133 30GB Maxtor drives on the controller. I set up a RAID 0 in the configuration, and all went smoothly.

However, Windows (XP Pro) does not recognize the full amount (60GB) of the RAID. It sees only half (30GB). I checked and rechecked the drivers. I have confirmed the RAID is set to RAID 0, not RAID 1. The drives are set correctly to master and slave. The RAID monitoring utility that comes with the mobo recognizes both drives and says everthing is OK. But, Windows won't see the full amount.

Any ideas of what is going on? Is this a windows glitch or is there likely a problem with the setup?

[THunDA]

Originally posted by flounder43
The drives are set correctly to master and slave.

I think they both have to be set as master..

Thunda

[wquiles]

Not only both need to setup as master, but they can't be on the same IDE cable - remember that in RAID 0 you are accesing both drives at the same time.

[ToiletDuck]

Both of those are wrong. A raid setup can be on the same cable and could be put on cable select. Go into control panel>administrative tools>computer management>storage>disk management

Once there look and see if on the right any of the drives are shows as unalocated or with a black bar above them. In order to run raid with windows XP (or at least when i've done it) you have to either install software that came with the card to do it or go there and activate the partition.

Duck

[THunDA]

Wouldnt having the raid on one IDE channel hinder performance too much having them reading and writing from same channel ?

And he seems to have a On Board raid setup.. not a pci raid card... shouldnt he have to just set the raid 0 in the raid bios and then install windows and press f6 during setup ?


Thunda

[theELVISCERATOR]

[QUOTE]Originally posted by THunDA
Wouldnt having the raid on one IDE channel hinder performance too much having them reading and writing from same channel ?

And he seems to have a On Board raid setup.. not a pci raid card... shouldnt he have to just set the raid 0 in the raid bios and then install windows and press f6 during setup ?


Thunda [/QUOTE

testing should show any difference..hmmmm

yes the disks must be raided in bios befores windows ever sees it,

and the F6 Boogie, have your raid drivers handy on floppy...

He was arguing the fact you CAN do it that way...(on one cable).
not necessarily best practice.........My first raid array is sata so you must use two...

[flounder43]

Originally posted by ToiletDuck
Both of those are wrong. A raid setup can be on the same cable and could be put on cable select. Go into control panel>administrative tools>computer management>storage>disk management

Once there look and see if on the right any of the drives are shows as unalocated or with a black bar above them. In order to run raid with windows XP (or at least when i've done it) you have to either install software that came with the card to do it or go there and activate the partition.

Duck

Good info. I went into the disk management, and yes, the one drive did have a black bar above it. I then activated it....hmmmm. BRB

*edit, I ended up having to delete the partition that it had put on the one drive, then I was able to partition the array together.

Thank you very much TD, you had the answer. I really appreciate it.

- Eric

[flounder43]

Originally posted by THunDA
Wouldnt having the raid on one IDE channel hinder performance too much having them reading and writing from same channel ?

And he seems to have a On Board raid setup.. not a pci raid card... shouldnt he have to just set the raid 0 in the raid bios and then install windows and press f6 during setup ?


Thunda

Yes, I think that I should have them on separate cables for best performance. I just didn't have it that way at this point because I have been trying to figure out what was wrong.

With regard to the F6 thing, well, this was not a new install, and I didn't feel like doing a new install...

Thanks,

- Eric

[Cjwinnit]

Originally posted by flounder43
Yes, I think that I should have them on separate cables for best performance. I just didn't at this point because I have been trying to figure out what was wrong.

It's definately a good idea to keep them on seperate channels as it helps a bit writing and reading.

Just so you know the RAID chip (Promise 02076?) can be upgraded to add ATA mode, so it works like a normal IDE chip. I have two CD-ROM's and two HDD's in my system with a Gigabyte 8IRXP and each has it's own cable. It's pretty fast :)

[flounder43]

I thought you guys might like some numbers comparing the performance using one cable versus using seperate channels...here ya go, not really that much difference, but there is some...

Same IDE Cable:

http://www.theforumisdown.com/uploadfiles/1203/samecable.JPG

Different Cables:

http://www.theforumisdown.com/uploadfiles/1203/differentcables.JPG

[flounder43]

By contrast, here is my single 80GB Seagate ATA100:

http://www.theforumisdown.com/uploadfiles/1203/single.JPG


So what's up? The RAID is somewhat faster reading, but WAY slower writing. I know I have tested a single ATA133 Maxtor and it was even faster than this one. What exactly is the real benefit of RAID? I am not realizing much advantage.


*edit On second thought, if you look at the smaller transfers, at the top of the graph, you see big differences...that must be the kick.

Look, for example, as the 2.0MB Read speed, 32,690MB/s on the RAID versus 16,200MB/s on the single drive. This is a big difference (2 times the speed).

[Cjwinnit]

I'm unsure, but you could try different queue depths, might complicate the RAID operatoins...

[shadowdr]

Your shoud set the total length to 32 and que depth to 10 and rerun the atto bench.If your raided drive does not show significant improvement Then you have a problem somewhere.