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I am wanting to replace my Operating sytem hard drive with 2 SSD drives. Well possibly just 1 but I am curious about doing 2 in a RAID-0 setup for even more improved speed. What exactly would I need to run 2 SSD drives in a raid0 setup?

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This needs an overkill tag. –  Mechanical snail Sep 20 '11 at 3:42
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I am curious about doing 2 in a RAID-0 setup for even more improved speed.

here's an article, that may be of interest to you:

RAID Performance w/ four Patriot Warp 2 SSDs - Up to 660MB/s

660 MB/s sounds tempting :)

besides the SSDs you'll need a RAID controller.

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sounds tempting and then you see the $600 raid controller –  basszero Dec 10 '09 at 20:19
    
the Warp 2 aren't exactly cheap either, 2 x 64 GB = $400 ... but who said performance comes free of charge? :) –  Molly7244 Dec 10 '09 at 20:27
    
The way those graphs top out at similar points suggests to me that the bottleneck for bulk read operations is not the drives but somewhere else - perhaps the controller. I wonder how well the same drives would do on a different setup, say two each on separate PCI-E controllers (or each on its own PCI-E controller) using software RAID (taking the CPU hit implied by that arrangement) to nit a RAID0 array together. If someone will buy me the drives I'll gladly perform many tests and publish the results! –  David Spillett Dec 12 '09 at 1:44
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As Molly points out, you can get incredible speeds from SLC SSD drives, using a PCIe interface. But for most people, this is terribly expensive, and the benefit from relatively cheap MLC drives with a regular SATA interface is still spectacular compared to HDDs (in some cases an order of magnitude greater). Bear in mind that random read/write speeds are often the most important factor for most desktop use, and sequential speeds are only relevant in certain situations.

This question also discusses the possibility of SSDs in RAID.

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Running two SSDs in a RAID0 config requires the same as two spinning disk based drives, assuming you are talking about SATA or PATA internal drives.

If your OS is Linux the software RAID support is pretty good and depending on your preferred distribution it is not difficult to install into such a configuration. Windows also does software RAID if you configure your drives as dynamic disks, though how you go about getting it to install initially into a RAID0 config or move it to one later is something I don't know (and it could be quite some hassle). A hardware RAID controller is another option. A good one will be more efficient, but expensive. A cheap one (especially one build on to your motherboard) will be "fake RAID" (a mix of the bad points from hardware RAID and the bad points of software RAID!) and probably best avoided.

The performance characteristics of SSDs will of course change the benefits you do/don't see from RAID0. As their seek time is effectively 0 compared to spinning-disk-plus-arm based drives you won't see the random access latency improvements spinning disks can get, though you will see throughput rates improve by about the same multiplier for most I/O loads. One important thing for RAID0/5/similar on SSDs: try make sure the block sized used by the RAID0 setup matches the block size of the SSD or a small multiple there-of and is aligned with said "physical" blocks, otherwise you will see lower performance than you could otherwise attain (particularly for write operations). See this discussion for a little more detail on that.

One of the many advantages of software RAID is that you can mix types between partitions on the same drive. When I next reinstall my netbook (for a clean shift to Ubuntu 9.10) I plan to try RAID0 its root partition (over its very slow internal SSD, an SD card that seems to run at much the same speeds for writing (a little slower for reading), and maybe a little USB reader like these with a quick uSD card in), but have /home and other areas where I might want to keep files safer in a RAID1 array built on other partitions on the same drives.

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