Advice on which Raid to use please

Ultim8

Ultim8

Ultim8

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Hello People,

Looking for some advice on what raid to use, im not a newbie to this and have used Raid 0 loads of times for performance machines. This time its for a server though and i currently have no raid on them and find that un-raring files and lag between them playing on my XMBC is painful now. I used to do it all on 4 x Raid 0 setup.

I have 4 x 1TB 7200.12's and 1 x 320GB (2 if needed) and im just using my old striker extreme and dont want to spend any money on a dedicated raid controller.

What i want to know is am i going to get better performance out of:

1 x 320GB OS & 4 x 1TB in Raid 5
1 x 320GB OS & 4 x 1TB Raid 0+1

I know raid 5 has parity and uses more CPU power but the machine is just gonna sit there doing nothing but streaming movies and music around the house. Its more the performance.

Im also toying with the idea of ditching the dvd-rw and putting the other 320GB in and raid 0 the OS. Will this make much difference to things like unraring or streaming movies if they are coming from the TB drives?

Cheers
 
If it's just a home media server, I'd say put the 4x1TB in RAID5, and have the 320gb for the OS. Performance will be fine even with motherboard RAID for that scenario, and if you're anything like me, you'll appreciate the extra space more than anything else (and the chance to expand your array up to 5x1TB drives in RAID5 for 4TB space - check to see if your motherboard raid controller supports online capacity expansion)

Performance wise, there wouldn't really be much point in having the two 320gb's in raid0 for the OS, wouldn't affect streaming speeds at all, and unrar performance is likely to be limited by your cpu before you hit the 320gb read limit.

If you don't see yourself using over 2TB, then RAID 0+1 is fine - same fault tolerence as RAID5, but with faster writes, at the cost of space.

One last thing, MFT limits partition sizes to 2TB each, so if you go raid5, you'll either need multiple partitions, or to convert the volume to a GPT disk (which can't be booted from btw), so check your version of windows supports GPT.
 
Last edited:
cheers Zarf and what kind of MB/S do you think i will get with raid 5 im guessing the raid 0 i will get around 160MB/S
 
It looks like you're going through the same decisions I went through a while ago. Network throughput can be a bottleneck, and remember the mantra "raid is not a backup".
In the end I decided to have a set of local disks on my main pc to unrar/organise on (using raid 0 if you want), and then to sync these periodically to the server. Works for me - quick unraring/organising and a full backup...
 
I would check that the RAID5 array (assuming it's a software based solution) can stream across the network fast enough for you. If you're running 10/100 it shouldn't be a problem, but if gigabit then it's likely the hard drives are going to be your bottleneck and I've seen some very poor RAID5 performance using onboard and cheapo RAID controllers.
 
Thanks for the response's guys I want to keep my new gaming rig for exactly that and the server for the donkey work ie Torrents, storage and streaming.

Im swaying towards the Raid 0+1 solution but would really like to know the speed im likely to get with 4 x 1TB 7200.12's in Raid 5 compared to the same 4 drives in Raid 0+1 config.

The mobo is a striker extreme and i believe the raid controller is a Silicon Image 3132.

And my network is all gigabit :)

Cheers
 
Ultim8 said:
cheers Zarf and what kind of MB/S do you think i will get with raid 5 im guessing the raid 0 i will get around 160MB/S
Click to expand...

read speeds shouldn't be too far off the RAID0 speed. Writes are entirely down to how good the motherboard RAID is, I had a quick look and unfortunately it seems the nforce struggles a bit, only getting ~30MB/s

Unless you do what i did and get a cheap perc 5/i hardware raid controller second hand, or just download freenas/openfiler for a decent software RAID array, it looks like you'll need RAID 0+1 to have any kind of performance.
 
hmmmm ok Zarf cheers for the info and I think I have a few 3ware 9650 controllers laying around at work somewhere any idea what speed they will get?
 
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