I have a question that is fairly wide open and I imagine the exact answer will be "well, it depends" This is really a getting started question and I expect I'll be going in multiple directions for answers. So here we go.
Is there a recommended free space percentage when setting up raids. Any by that I mean, I have a six 300GB drives, I configure them for for a raid 5. When I create the logical volume, is there a reason to not allocate all 1.5TB. Say I only allocate 80% of that space, so let's say I allocate 1.3TB and leave 200GB of space out there. Does the raid controller\System ever use that 200GB of space for recovery blocks etc etc.
Now I know there are probably a dozen questions people have on that. Is it hardware or software, who's the vendor, Is it SCSI\ATA\SAS disks. is it virtual arrays. I am looking at more tradtional style raids of hardware and software and a little less on the new Virtual arrays, but I'm interested in it all.
The answer to those questions are, you tell me. I'm looking for any example of where a software SATA raid would want\need to have 20% unallocate space but a SCSI hardware raid does not or maybe a Software SCSI does, but a Hardware SATA doesn't.
Again a fairly wide open question and I'm just looking to understand the different needs of the different style of raids. Any pointers\links that you have from various vendors would be wonderful.
Edited by Daleynoy, 05 April 2013 - 10:19 AM.