On 02/08/13 17:57, Mark Hahn wrote: >> solid devices as well (also expensive however). I think Micron also has >> a native PCIe device in the wild now, the P320h? Anybody know of other, >> native PCIe devices? > > I'm not even sure what "native" PCIe flash would look like. Do you mean > that the driver and/or filesystem would have to do the wear-levelling and > block remapping and garbage collection explicitly?
No, this is referring to the internal protocols of the SSD. The SSD is just exposing a given protocol, but internally is managing many discrete storage devices (think baby RAID and micro-os in a box). Right now, many SSD manufacturers are just SSD "repackagers" (including OCZ to my knowledge). They buy a controller design from one place (some make this component), SSD packages from someplace else, some channel controllers, etc, etc, and strap it all together. Which is totally fine, but the problem arises because the volume for NAND flash packages are for SATA based drives. This results in most of the NAND packages within to export a SATA protocol. This requires these re-packaging companies to have to translate to and from the SATA and PCIe protocols. For another explanation, please see the fourth paragraph of: http://www.anandtech.com/show/4408/microns-p320h-a-custom-controller-native-pcie-ssd-in-350700gb-capacities Hopefully this explains better the issue I'm referring to. Managing the raw flash at the filesystem or driver level is an option, but not what I was talking about (nor what is currently in vogue right now, to my knowledge). To be fair, I do like OCZ's solutions for retail SATA drives. But the jump from that protocol to PCIe, if you are going to make it, needs to be made with some consideration. It's more expensive and is a more diverse space in terms of "real" performance provided by the various vendors. In even a year or two this probably won't be the case, but right now there is a lot of junk on the market. Just my 2c though, ellis _______________________________________________ Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
