Conclusive ThoughtsAnd the ideal stripe size for RAID 0 with SSDs is:
The default 128k settingWell, you either decide that this article was a complete waste of time, or think of it as a confirmation that the default raid stripe size turned out the offer the best balanced performance throughout the different benchmarks.
It was fun to see a RAID 0 with 4k stripe size outperform the rest by a factor of 7x, but that was only in a single benchmark, more than 1200 bench runs later though we can safely make the assumption that you should not configure a RAID 0 array with a stripe size smaller than 32k.
After throwing all the random, sequential, threaded, and asynchronous read and write tasks to the RAID 0 array with different stripe size. Here is the final chart:
Performance wise with RAID 0 we saw a performance boost over single SSD up to 250% in certain tasks; on average it will give you a 100% boost in all disk related tasks; so it’s certainly a recommended path if
performance is your main goal.
Cost wise buying two smaller SSD drives will be more expensive than one larger SSD; but if you invest a bit of time configuring your RAID array you will have a faster system than what was possible with the single SSD.
Reliability of a RAID 0 array with SSD is of course a lot better than what was possible with HDDs, but don’t go thinking it’s a foul proof plan. SSD can still malfunction, RAID array can still go corrupt and moving between systems with a RAID 0 array install poses an extra challenge. Also don’t forget that TRIM doesn’t work on RAID arrays, so you’ll have to manually perform the necessary steps if you want your RAID array to perform at its best.
The OCZ SSDs drives used in this article are already a bit older, the
Vertex 30Gb costs about ~€130, and doesn’t have a 30~40mb/s write cap like some other entry products recently launched. When you put two of these drives in RAID 0 we saw speeds close to 200mb/s; definitely enough for most power users.
If you add more members to a RAID 0 array you’ll see nice performance scaling; but to get the most out of it you’ll have to invest in a dedicated RAID controller which has onboard cache and PCI Express interface; this will allow you to build
your own 2000mb/s disk volume. OCZ and other manufacturers have been playing around with this approach (RAID controller + SSDs in RAID 0)
since Cebit last year, but as with everything new, flashy, shiny and speedy, it doesn’t come cheap.
If you do want to take a peak at the future with a limited budget and you have an interest in SSDs and RAID, we hope this article can be of use to.
We like to thank
OCZ for allowing us to stress test their Vertex drives, until next time, thank you for reading!
I'll be upgrading soon (or at least after you publish the new Cooler roundup ) and I'm undecided as to an OS drive.
260 Euro can get you a very fast, single, simple to use SSD.