4 drive RAID 0

[SiM]

Has anyone tried it?

Thinking of trying software raid 0 with 3 or 4 of the new, fast 320GB drives

How does performance compare to 3 or 4 drive raid 5?

[shaithis]

Performance would be good but I would never run a 2 drive raid 0, let alone any more drives.

1 drive dies and you lose the data on them all, really only see the benefit in raid 0 if its mirrored as well (costly) or the data is expendable (swap and temp files, which 2-4 drives is complete overkill for)

[aidanjt]

Marginally better in reads, a lot better in writes. Haven't tried it personally though. Since anything over 3 disks i'll end up sticking it in RAID5.

[Flewis]

Raid 0 with more than 2 drives is asking for trouble, if one goes you lose all of your data. To me raid 0 with 2 drives is more risk than its worth. Raid 5 gives you some protection of your data and seems a better option to me.

[SiM]

Thinking about doing it purely for the e-peen factor... Would of course back up the whole array, at least once a week, to the NAS once its all set up.

[aidanjt]

You still lose a disk to parity data, and calculating that parity data adds additional overhead you might not want if you don't store anything important on the array.

[shaithis]

Is it for a benchmark or just "because"?

It its just "because", then try raid 5, reads are very fast, writes not so good. But if you read from your disk more then you write to it, then raid5 can be excellent.

You can always keep a raid 0 somewhere if you do any AV work (or other write-intensive tasks), can be a nice scratch drive for rendering down to.

[SiM]

Hmmm... I think I will give it a go with 3 drives. I will probably reformat and convert to RAID 5 after though as I don't need that much space anyway and the read is more important than write for me...

[peterb]

You still lose a disk to parity data, and calculating that parity data adds additional overhead you might not want if you don't store anything important on the array.

No parity on a RAID 0 (Or were you talking about a RAID 5 setup?)

[SiM]

No parity on a RAID 0 (Or were you talking about a RAID 5 setup?)

He was saying why people might choose raid 0 over raid 5... so yeh he is talking about raid 5

[SiM]

Went for 3 drives in the end as I don't need the space of 4...
What do you think?

I was expecting faster... I suppose you shouldn't measure your epeen, before its fully erect

[Mblaster]

It's barely faster than my 2 disk RAID0 array, would've thought the speed increase would be fairly linear on a benchmark like this.

[LegacyOne]

Went for 3 drives in the end as I don't need the space of 4...
What do you think?

I was expecting faster... I suppose you shouldn't measure your epeen, before its fully erect

Do you have Write-Back Cache enabled in the Matrix Storage Manager.

My fastest RAID 5 is about 10MB/s slower on average.

Your My System drop down lists '3 x 320gb single platter in Raid 5' but to get 960GB in HD tach would need to be RAID 0?

[SiM]

Yeh, its disappointing... maybe its because software raid generally is limited by something else... These are single platter 320gb too... I bought these especially for a fast drive array

Its raid 0, but I am going to reinstall it as raid 5 soon as I don't need that much space...

Will look into write back cache... I don't know what it is... (haven't done raid since nf3)

Edit: I chose 128k strip size. It is what the setup recommended for raid 0

[SiM]

Do you have Write-Back Cache enabled in the Matrix Storage Manager.

Full marks to you

Is that better
Look at my epeen everyone
CPU usage is pretty high though....

[mikerr]

Something to aim for:

Yes, 0 access time and a few thousand quid raid of 5x mtron ssds...
http://www.nextlevelhardware.com/storage/battleship/