RAID 0 speed improvement

Question

I've got a free Samsung EV0 840 120GB from my uncle. I already got a 250 EVO 840 in my computer. Now I was asking myself if I got a significant speed boost if I put them in RAID 0. I know the total volume size will be the double of the 120 drive, but I don't need more storage I just want to try this for a speed boost.

So will the speed improvement be noticeable or should I use it just as an extra drive?

Answer 1

RAID-0 can theoretically give up to twice the IOPS of each individual disk, but it doubles your risk of catastrophic data loss. If either disk fails, you effectively lose all of your data. I say theoretically, and it's really important in the case of SSDs, because doubling assumes zero-latency coordination from the RAID controller, which is impossible. A really good RAID controller gets you closer, but SSDs already have incredibly low latency and high IOPS.

Individual disks will give better performance if they are at capacity performing independent workloads, particularly if those workloads are predominantly sequential read/write workloads.

RAID-0 disks will give better overall performance for less predictable workloads since you get almost twice the IOPS. If you don't need the data, just the performance for mixed workloads this is a reasonable option.

I strongly recommend against using RAID-0 even on a personal computer.

I would just use it as an extra drive, or even sacrifice disk performance for RAID-1 to get disk failure resilience.