RAID 0 using different drives

[sailingtaz]

Newb question:

I?ve two drives I would like to setup as RAID 0:

HD #1: 320GB 7200 RPM
HD #2: 240GB 5400 RPM

Assuming in RAID 0, storage capacity will be 240gb and combined performance will be equivalent to having two 5400 RPM HDs.

Am I correct?

 

[RebateMonger]

Total storage capacity will be 2x240 GB.

 

[Laputa]

Depending on whether you set them up as RAID-0 spanned or RAID-0 striped. Spanned volume = 560GB total space, no performance gain. If one drive got tossed, you have whatever is left on the other drive to recover. Striped set = 480GB total space. Half of the data will be on one drive and the other half on the other. Performance wise, data transfer is supposed to be faster since the data are coming from two drives at once. The down side is that if one drive goes south, just kiss the drives and say good bye to the data that you stored on them cause everything you can recover will be half corrupted.

 

[Nothinman]

Depending on whether you set them up as RAID-0 spanned or RAID-0 striped

RAID0 is only striped, spanning has nothing to do with RAID of any level.

 

[Cr0nJ0b]

I would say the total capacity would be:

2 x 240 = 480 + 80 = 560.

You would create 2 volumes, one from the RAID0 stripe and the other from the remaining capacity on the second drive.

of course, this is assuming that you are using some type of smart RAID like software RAID or a higher end RAID controller. I think that standard Mobo raid chips will just cut down the usable on one of the drives to match the others.

By the way, I do this all the time with SW RAID on Linux.

for example, I have a 5 drive RAID set with 3 (750GB) and 2 (500GB). I stripe them for a 5 x 500GB set and a 3 x 250GB set. Works fine.

 

[mtnd3vil]

HD#2 is bad news.
This will likely hurt the decent performance that you DO get from the single 320GB.
Just do some simple benchmarking both ways and I'm pretty sure it will be obvious.

IMHO the preferred configuration based on what you've got would be to install your OS to the 320 and use the 5400RPM drive for simple data store.

 

[RebateMonger]

Originally posted by: mtnd3vil
IMHO the preferred configuration based on what you've got would be to install your OS to the 320 and use the 5400RPM drive for simple data store.

Yeah, any possible speed gain from RAID 0 will likely evaporate because of the 5400 RPM disk. PLUS you lose total capacity.