Is RAID 0 really faster for SSD's?

[patseguin Global Moderator]

I have an SAS controller onto which I have 2x 256GB SSD's in RAID 0 and 2 hard drives in RAID 0. BIOS post takes longer because of the card but once the Windows boot screen comes up it takes as long as 20-30 seconds to boot. my cheap HTPC I built with an i3 and and SSD connected to the motherboard boots so fast, the flag doesn't even have time to form (Windows 8). Probably from power on to windows is like 5-6 seconds.

[xendrome]

Should be, my RAID 0 boots Windows 7 in about 5 seconds after the bios.

Did you fresh load the OS on the Raid 0 or image it, maybe you have an alignment issue...

[djdanster]

That's funny I was thinking the same thing. My RAID 0 SSD setup (2x60GB) takes longer to boot up than some mechanical drives. I'm starting to think it's more to do with the CPU. I've tested against my phenom 955 with RAID 0 ssd against an i3 mechanical hdd and the i3 won...

[SuperKid]

You should see an improvement, I only have a 256GB SSD with OS X on and it boots faster than your RAID, about 10 seconds max to desktop with all apps open using an i7.

[Vice]

The thing that makes SSD's so fast is their IOPS or Input/Output Operations Per Second. It's not really the bandwidth that makes it feel fast. By putting SSD's in raid you're actually increasing the latency and lowering the IOPs to get increased bandwidth.

Raiding SSD's thus benefits large file read/writes like video editing, content creation in general, normal large file transfers. But it can reduce performance for things like booting and small file transfers. At worst you'll see a performance deficit and at best the performance will remain the same.

I did a lot of testing on this recently by trying a single SSD then RAID0 with two identical SSD's then RAID0 with three identical SSD's - Each time I added an extra drive to the RAID group the latency went up and IOPS went down. Of course throughput went up but how often are you transferring very large files and how often is 470MB/ps write not enough?

In my opinion keep your SSD's unraided, all my own testing says there's no benefit beyond throughput and many tasks including booting actually took longer and depending on the RAID card you have you may even get an extra boot screen to sit through that can double, triple or quadruple boot times.