Deconstructing a RAID0 array

Marakith · 13 Oct 2006 at 15:18

Hello,

I have a RAID0 array with a fresh install of Windows on it. I don't think I'll be sticking with the RAID0 array as I'm not convinced the performance gains justify the price. The gains have been microscopic and the price difference is over £100.

Is there a fast way to consolidate the data blocks back onto one drive to save me having to reinstall Windows?

I'm running the Raid Array on the Intel drivers that came with my P5W64D. I'd also be happy to consider keeping the array - perhaps there's a better way to set up the array - using the Marvell array, perhaps? (if so - how do I move to the other controller without a new install) Or maybe you can suggest ways to optimise what I've got here.

Many thanks in advance!

semi-pro waster · 13 Oct 2006 at 16:07

You could probably 'Ghost' the array across to a second(third physical I guess) hard disk as the process would the same as for any logical hard disk.

I don't think you will be able to just move from the Intel controller to the Marvell one without a re-install, they are normally quite dependant on the controller.

Optimising isn't normally something that can be done after the initial set-up as far as I know, usually the stripe size is the most important single determining factor in the arrays speed and you can't alter that afterwards.

ByteJuggler · 13 Oct 2006 at 16:07

What stripe size do you use? Might consider changing that. Also, difference controllers do sometimes have differing performance profiles. The Intel one by all accounts tend to be very good however.

In terms of consolidation: You'd need a seperate/spare drive to move onto from which you can then move back after un-RAID'ing. It can be done but might be tricky. You also positively want to back up everything before starting.

snowdog · 13 Oct 2006 at 16:10

?

100 quid extra for raid 0?
How can that be raid zero gives total ammount of space of 2 hdd's (2x250gig = 500) and it costs just as much to have 2 standalone 2x250 gigs (just example), its about 80% as fast if it comes to loading, copying, etc...
So basicly, raid 0 is free if you have 2 hdd's, no extra costs so i dont know what you mean with 100 quid, unlless you dont need 2 hdd's offcourse.

Dont you mean raid 1 (mirroring)?

Intels raid controller is faster as promise as far as i've heard.

Marakith · 13 Oct 2006 at 16:41

I don't really need the extra space. I have a 132Gb "maindisk" now. Bit of overkill tbh. To me, that £100 is wasted atm. Plus there's an increased risk of breakdowns in a RAID0.

My stripesize is 128kb. Should I consider larger or smaller?

Thanks for the great responses so far!

snowdog · 13 Oct 2006 at 16:48

Marakith said:
I don't really need the extra space. I have a 132Gb "maindisk" now. Bit of overkill tbh. To me, that £100 is wasted atm. Plus there's an increased risk of breakdowns in a RAID0.

My stripesize is 128kb. Should I consider larger or smaller?

Thanks for the great responses so far!

Ahhh k, ive heard 32 kb is most popular for windows etc...
Also the risk of breakdown isnt that big, just twice the usual.
Anyhow if you dont need 132 gigs i suppsose sell one of the 2, first try a smaller stripe size if its better, if you still think its too slow you either need more hdd's in the array or just a faster hdd.
Personally I cant imagine how people keep their hdd's so empty (132 gigs would be full in a week in my pc) , i have to buy a new hdd like each 3 or 4 months to have empty space left.

Marakith · 13 Oct 2006 at 18:00

snowdog said:
Ahhh k, ive heard 32 kb is most popular for windows etc...
Also the risk of breakdown isnt that big, just twice the usual.
Anyhow if you dont need 132 gigs i suppsose sell one of the 2, first try a smaller stripe size if its better, if you still think its too slow you either need more hdd's in the array or just a faster hdd.
Personally I cant imagine how people keep their hdd's so empty (132 gigs would be full in a week in my pc) , i have to buy a new hdd like each 3 or 4 months to have empty space left.

Well, if the consensus is that a 32k stripe will make things faster, then I might give that a go. Since each reinstall of games is a few hours' work, I'd love to see some numbers to beck it up...

As for keeping my disk free, I've got another drive that will work as the storage drive. I'll be keeping all my docs and emails etc on that drive. Plus I have a NAS unit on the home network.

Cheers!

Marakith · 14 Oct 2006 at 00:30

Just for info, here's a comparison of my Barton (1 Raptor OS Disk) and Conroe (1 Raid0 Raptor Array 2x74Gb Disks):

Barton

Conroe

What's weird is that Windows XP takes twice as long to load up on the Conroe than on the Barton!

What do you reckon?

silversurfer · 14 Oct 2006 at 03:14

Raid has a higher seek time I think and windows will load lots of fairly small files.
I guess raptor is best used singularly, its allready dam fast

Marakith · 15 Oct 2006 at 19:20

Well,

Here's the rig tested out with just one Raptor. Quite a difference on the average transfer rate:

Still, Windows loads like a dog. I think it is th ASUS chipset drivers as until then everything was fine.

Not seen much degradation in gaming performance, so I don't think RAID0 gives me much of a boost, to be honest.

silversurfer · 15 Oct 2006 at 19:28

Well the seek time for the raid looked low anyway its just Iam told times rise in a raid but maybe thats more the case for dissimilar hdd.

You should defrag, run bootvis. If you have the space, wipe it all and start again. How often do you copy gig+ sized files, thats what your setup looks like its really going to improve most

Marakith · 15 Oct 2006 at 20:42

silversurfer said:
Well the seek time for the raid looked low anyway its just Iam told times rise in a raid but maybe thats more the case for dissimilar hdd.

You should defrag, run bootvis. If you have the space, wipe it all and start again. How often do you copy gig+ sized files, thats what your setup looks like its really going to improve most

It is a new build. I've just reinstalled and defragged several times today.

As for your copying question, the rig is mainly for gaming. I'm not convinced that the RAID array makes a big difference, so I've gone back to a single Raptor.

I've also seen threads on the 'Net about SP" slowing things down and that appears to have happened with this PC.

I'm going to look into sorting out the memory latency settings etc. Currently, these are not looking too good.

Thanks!