Limiting factor in RAID0?

ohhgourami

Distinguished
Sep 6, 2011
126
0
18,690
What if I have a drive that should write at 300mb/s and 500mb/s. If in RAID0 should they run more like 600mb/s (where the 300mb/s is a limiting factor) or will it be more like 800mb/s?
 
The Read/Write performance of a RAID-0 array is based upon the drive with the slowest Read/Write speeds; so if you RAID-0 a 300MB/s drive and a 500MB/s drive your speeds would max out at 600MB/s.

The capacity of a RAID-0 array is also based upon the drive with the smallest capacity.
If your RAID-0 a 60GB drive and a 240GB drive, the total capacity of your array will be 120GB (60GB x 2).
 
^ Not true
Concur with WyomingKnott, I do not recommend raid0 SSDs used as a Boot + program drive. You chouice if used as a Data drive.

To answer your question on speed. For sequencial read/writes. Over all will depend on (a) strip size and (B) the size of files being called. For example using a 64 K strip. If the file size is less than 64 K then all of the file will be on one drive and the speed will be dictated by that drive. If the file is split (<64 K) then the speed will be dependent on both drives, part of the file would be at drive 1 speed and part of the drive would be at drive 2 speed and will be somewares between the sum of the two but less than 2 x the fastes drive.

Raid0
.. Improves Sequencial performans, the LEAST important matrix for an OS + Program drive. Important for a data drive when working with LARGE file structures.
.. Does NOT improve access time
.. Very litel improvement for the more important 4 K random read/writes.
Improves sequencial speeds