RAID 0+1 performance

[Agent_Skorch]

Has anyone seen a comparison of HDD controllers that show performance benchmarks strictly using RAID 0+1 arrays ?

[drizzt81]

try tweakers.net, but they mostly have raid 10.

[InorganicMatter]

I'm curious as to the performance as well.

Of course, this raises the question: do you stripe the mirror or mirror the stripe? :D

[unhappy_mage]

Stripe the mirrors, of course. It helps a tiny bit at the 4-disk size, but if you've got say 10 disks it's the only way to go.

Performance doing what? If you're running a database, you'll find a lot of benchmarks - for the SAME reason :p If you're asking in terms of games, I don't think you'll find a whole lot of them. Not many people want to pay for 4 disks and end up with the capacity of 2, and raid 0+1 may not provide the performance boost you're looking for.

http://www.hardfolding.com/ftag1.php/mem/150072.png (http://www.hardfolding.com?go=38&tm=33&id=150072)http://www.hardfolding.com/utag.php/mem/1392.png (http://www.hardfolding.com?go=36&id=1392)

[Agent_Skorch]

I'm referring mainly to gaming applications. I have an unfortunate history of having failed drives in RAID 0, thus losing the whole ball of wax. I've tried Casper XP to " ghost " the RAID 0 array to a third disk and it actually worked one time, but I'm looking for better than single-drive performance with a built-in safeguard against a single drive failure. I have no qualms about buying 4 drives and getting 1/2 capacity. That's why I wished to see the comparison of RAID 0+1 ( or 1+0 ) on a head-to-head controller performance basis i.e. nforce4 vs. Radeon Express vs. VIA, and so forth and so on. I'm planning to put together 4x Raptor 150's in either 0+1 or 1+0 on a MB that supports an FX-60 and would like to know which chipset/controller would render the best performance. Another factor may be that I plan on having 2 GB dual-channel memory with a 4 GB iRAM drive to use exclusively as a Windows paging file. I hope that clears up what I'm trying to do. Thanks.

[unhappy_mage]

So you're spending $1200 on a hard drive setup, but only getting $200 worth of ram? I think you'd be better off with a couple more gigs of memory, even with the iRAM. I'd suggest a pair of raid 1's rather than raid 0+1, and put games on one array and Windows etc. on the other one.

This (http://techreport.com/reviews/2005q4/chipset-raid/index.x?pg=2) seems to be the closest I can come to what you're asking about, and the utter lack of real-world benchmarks is somewhat disappointing. My favorite review (http://tweakers.net/reviews/557/21) only does "desktop" benchmarks and doesn't test with any games, but they do try a wide range of raid controllers in many raid levels, so you may be able to draw some conclusions from that.

I hope you're thinking of this as a last-10-percent kind of thing. You had better have SLI/xFire in this rig, nothing else warrants the huge expense on hard drives for only 300gb of storage. You might be better off with an 8gb iRam and a single Raptor; load Windows on the raptor and put your games on the iram. Put 4gb of memory in the main system. I think 4 raptors in 0+1 is overkill and you won't see much difference between that and a pair in raid 1, but an iram is definitely going to be faster.

http://www.hardfolding.com/ftag1.php/mem/150072.png (http://www.hardfolding.com?go=38&tm=33&id=150072)http://www.hardfolding.com/utag.php/mem/1392.png (http://www.hardfolding.com?go=36&id=1392)

[TheDoucheMan]

So you're spending $1200 on a hard drive setup, but only getting $200 worth of ram? I think you'd be better off with a couple more gigs of memory, even with the iRAM. I'd suggest a pair of raid 1's rather than raid 0+1, and put games on one array and Windows etc. on the other one.

This (http://techreport.com/reviews/2005q4/chipset-raid/index.x?pg=2) seems to be the closest I can come to what you're asking about, and the utter lack of real-world benchmarks is somewhat disappointing. My favorite review (http://tweakers.net/reviews/557/21) only does "desktop" benchmarks and doesn't test with any games, but they do try a wide range of raid controllers in many raid levels, so you may be able to draw some conclusions from that.

I hope you're thinking of this as a last-10-percent kind of thing. You had better have SLI/xFire in this rig, nothing else warrants the huge expense on hard drives for only 300gb of storage. You might be better off with an 8gb iRam and a single Raptor; load Windows on the raptor and put your games on the iram. Put 4gb of memory in the main system. I think 4 raptors in 0+1 is overkill and you won't see much difference between that and a pair in raid 1, but an iram is definitely going to be faster.

http://www.hardfolding.com/ftag1.php/mem/150072.png (http://www.hardfolding.com?go=38&tm=33&id=150072)http://www.hardfolding.com/utag.php/mem/1392.png (http://www.hardfolding.com?go=36&id=1392)


He would probably just be better of with one 150 and a larger storage drive. Any raid controller built into the chipset will be software based. So whenever you do something on your array it is sapping cycles from your cpu.

I second going with more ram. With enough ram, the harddrives come out of the performance equation for gaming.

If you are really afraid of data loss, just ghost your system drive onto another drive everyday. That way you won't hurt your gaming performance and you will always have a no more than one day old backup of your system. Because with raid1 there will be a performance hit, and with raid0 the majority of people don't even believe that there is any benefit. How often do you sit down to a nice long session of playing a harddrive benchmark?

[Agent_Skorch]

Interesting alternatives. To clarify, I do intend to have XFire on two X1900XTX's and the reason that I chose 2 gig of RAM is that I have "heard" that 4 GB cannot be seen by Windows in its entirety on a 32-bit OS. Also, using 4x 1 GB sticks allegedly will run only single channel at a 2T command rate and I considered that a limiting factor. Perhaps I should rethink the RAM issue. You guys did greatly enlighten me on configuration options. Thank you. Additional information welcome.

[Agent_Skorch]

One other thing. In reviewing the benchmarks, I see that CPU usage is always < 5% during array activity. Would that be a definitive concern of software RAID vs. Hardware ? The FX-60 should have enough horsepower to handle that without hiccups, should it not ?

[unhappy_mage]

With raid 0 or 1, the load is low enough that it shouldn't even be an issue. The only type of raid with appreciable cpu load is raid with parity, like raid 5. A good driver-based raid will be as fast as fully hardware-based. And the FX-60 will have plenty of power to deal with anything, I imagine ;)

I hadn't heard that (single channel, 2t) about 4 1gb sticks. It is true that you wouldn't see all 4 GB; 32 bit machines (I assume you're going to be running 32-bit windows) can only see 3.75 GB. But 3.75 is still way more than 2. You might also look at some high quality 2gb sticks; I'm not sure if you'd be able to find nonecc/nonreg 2gb sticks, but your motherboard might support registered memory and ecc, so that'd be a non-issue. I don't know much about "performance" ram, though; when I bought this machine I got 512mb of really expensive stuff - corsair xms 3200ll, about $200 at the time - and it was a bottleneck. Adding another 512 of megacheap stuff fixed the problem. Moral of the story, as far as I'm concerned, is more is better.

http://www.hardfolding.com/ftag1.php/mem/150072.png (http://www.hardfolding.com?go=38&tm=33&id=150072)http://www.hardfolding.com/utag.php/mem/1392.png (http://www.hardfolding.com?go=36&id=1392)