Raid-o

[Pedro Estarque]

Ok, I know this has probably been asked a million times already but I couldn't find it anywhere so here it goes.
I have a G4 800 with a 40GB and a 80GB HD plugged in the same IDE controller ( the one that came with my mac. )
I was wondering if I could split the 80GB disk in to two 40 GB partition, and make a 80 GB RAID 0 disk with the other one. Something like this:
Disk one: 1st 40GB partition + 40 GB disk =80GB RAID-O
Disk two: 2nd 40GB partion
Can it be done? And probably the most important question, is it worth it ? I know software raid ( disk utility 10.2) isn't the best solution, but I can't afford any other right now. Do any of you know any graphics comparing I/O read/write performance differences?
Thanks

 

[acj]

Yep

It can be done, and software RAID is often faster than hardware raid, although it taxes the CPU. RAID 0 doesn't calculate parity though so it doesn't slow things down much.

 

[Pedro Estarque]

Re: Yep

Originally posted by acj
It can be done, and software RAID is often faster than hardware raid, although it taxes the CPU. RAID 0 doesn't calculate parity though so it doesn't slow things down much.

Thanks. But how much faster? I mean I'll have to backup everything , format reinstall etc.
Do you know any benchmarks? 10%, 20% wouldn't make much of a difference.

 

[lewdvig]

almost 25 additional Xbench marks for my machine (72 vs 96)

 

[legion]

Hardware RAIDing: NO. Logical disks are not supported (they would be detrimental to performance and the original intent of RAIDing: redundancy.)

Software RAIDing, probably (though it will tax your system since the RAIDing isn't handled by a controller but by your processor.) I wouldn't use, however, the second partition (the one you've set up as non-RAIDed) at the same time you are using the RAID volume because you'd definitley kill the performance for both the RAID 0 setup and the secondary partition access (after all, there are only so many read-write heads available) Finally, RAID 0 is a very risky RAID setup in the first place (risking the possibility of losing all access to your data since there is no redundancy and you're spreading the information over the two drives.) In this case, if something goes wrong, you'd lose not only all the info on the RAID setup but also on the secondary partition. You can pretty much kiss everything goodbye. It'd be cheap and give you higher performance and at least not deterioate your file security any more than RAID 0 already does, if you just pickup another 80GB drive (or 40GB drive) and set them up on their own IDE controller (with ultra-DMA access on) and RAID them. You could probably do all of this under $100 (plus you'd get more space.)

 

[Pedro Estarque]

Thank you all for the tips.
Question to lewdvig: did you get this performance boost without any additional hardware ? If you did, it might be worthy since I already have to back up everything once a month anyway.