Velociraptor + Raptor in RAID0

dechy

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Well, this definitely isn't something I was expecting; WD replaced a dying 150GB first-gen Raptor with a brand spanking new Velociraptor (not even refurbished, as most other drives that fail get replaced with!!).

I've almost always ran RAID0 any drives since they started to use on-board controllers, but now I'm faced with a weird dilemna.

Well, for one, my damn W7 RC is bugging me to re-install in the next 3 days :p But the obvious reason why I'm here is because I'm not exactly sure what kind of weird performance I'd get from a top of the line 10k RPM consumer HD paired to a "non-raid friendly" (apparently, as WD later released the more "raid-friendly" Raptors after buying mine...) "slower" HD. I almost wish both drives had failed lol!

I'm thinking I'd lose out on the Velociraptor performance by pairing those 2 together, so I'm pretty much leaning towards not RAIDing them even though I'm sure it would still be faster, but I'm just wondering if I'd hit some quirky behaviors... I'd hate to have to build up an OS again in a week after going through the motions...

Any insights/experiences or comments on this?

Thanks
 
Solution
The velociraptor has higher data density compared to the older raptor. when you combine that with the smaller physical plate and the 10k spin rate drive performance increases dramatically. I'm sorry my geometry is far to rusty to show why mathematically. Take a look at these benches. compare the single velociraptor to the raptor X (also a 150GB 10k rpm drive) you'll see the velociraptor either comes remarkably close or best the raptor raid 0 raid.

http://www.maximumpc.com/article/the_new_fastest_hard_drive_ever

tikrjee

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What he/she said

I wouldn't risk it either. Too many chances for instability. You'll get some good performance from the Velociraptor alone, anyway. Besides, using the "slower" drive for storage would still be faster than what most people use as a storage drive :D
 
I am looking at this from another point of view....Apparently it is not a big deal for you if a drive dies in RAID0. You are not here complaining about how to recover your data like most RAID 0 users end up doing. So you have learned to use RAID the proper way, and store important data somewhere else, right?
If it were me, I would just put the 2 drives back into RAID0 like you had them. There is no more chance of anything going wrong than you had with the first 2 identical drives. And if you are used to the throughput of 2 Raptors, I am afraid you are not going to be very happy with them split apart. I could be wrong, but that is my 2 cents.
 


What specs are you thinking of? I was not aware that the Velociraptor in reality was any faster than the old Raptors? It might have slightly better sustained thoughput, than either of the older Raptors alone, but by its self it will not be anywhere close to what 2 Raptors in RAID will do. And I don't believe there is any difference in access times, this is mainly relevant to the 10,000rpm that both the old and the new drive runs at, so it is about the same as well.

So I am just curious, (not meaning to offend or anything) how will the single drive outperform the 2 older drives in RAID? (though I grant that the 2 drives in RAID won't be a huge improvement over the 1 drive,) I just don't see how the 1 drive could be faster than 2 of them in RAID? If you are thinking of the SATA 150 vs the 300 interface, that really won't be much of a factor. A single Raptor or Velociraptor cannot even saturate the bandwidth of the SATA I -150 interface.

 
The velociraptor has higher data density compared to the older raptor. when you combine that with the smaller physical plate and the 10k spin rate drive performance increases dramatically. I'm sorry my geometry is far to rusty to show why mathematically. Take a look at these benches. compare the single velociraptor to the raptor X (also a 150GB 10k rpm drive) you'll see the velociraptor either comes remarkably close or best the raptor raid 0 raid.

http://www.maximumpc.com/article/the_new_fastest_hard_drive_ever
 
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dechy

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That MaximumPC link with the 2nd chart is a good eye opener; I'd lose out on average write if I had the Raptor X, but mine were the gen before that even, so it would probably be even or higher with the single Velociraptor.

I was skeptic as first, I knew the Velociraptor were a good step above the Raptor / Raptor X series, but to nearly equal a Raid 0 config of it's predecessors is quite good. A few other sites, put the Raptor X in RAID in front of a single Velociraptor, but not by as much as I had though.

And indeed, I was caught once by a failing Raid 0 array a long time ago; never again. Mirrored NAS + DVD backups for the REALLY critical stuff fixes that now... the OS & saved games can go to hell if it all blows up :p

Thanks for the input people.
 
That is astounding, it is astounding to the point that I think their test favors the Velociraptor a little too much. A quick Google search (The Raptors and Velociraptors have been benchmarked to death) you can find numerous benchmarks that put the Velociraptors at about 160mb/s average read and write speed, and the Raptor X's at about 135mb/s in RAID 0. And PCMark 05 as the benchmark test? I dunno, I simply don't think much of this "test". Oh well.
While there is a difference, the difference is not as night and day as this article shows. Saying all that, I am not a big RAID fan, (I ran RAID for years, finally gave it up) personally I would do just exactly what has been suggested, and run the drives as 2 separate units myself. I just find that particular link's results a little skewed compared to most other tests you see.
But, you had the 2 raptors in RAID0, so if I were you, I would try it both ways, run your own benchmarks, draw you own conclusions, then come back and let us know your findings! It would interesting to hear how it worked out for you.