On 19/02/13 23:46, Chris Murphy wrote: > > On Feb 19, 2013, at 3:41 PM, Stan Hoeppner <stan@xxxxxxxxxxxxxxxxx> > wrote: > >> On 2/18/2013 9:01 PM, Chris Murphy wrote: >>> Assuming HDD only, is there broad use case for RAID 4 that RAID 5 >>> isn't equally or better suited for? >>> >>> What about making the parity drive an SSD, keeping the other >>> drives HDD? Raid 4 has no good uses as a final format for a raid layout - raid 5 is better in every way. However, raid 4 /is/ useful as an intermediary format for md raid, during operations like re-shaping and re-sizing. It is more like a raid 5 with an unusual parity layout (md raid also supports raid 6 with a number of different parity layouts for the same reason). >> >> Why are you revisiting RAID-4? > > Because it's offered in Fedora 18's GUI installer. Fedora is a distribution aimed at experienced users and tinkerers, so it tends to include all sorts of weird opinions in the installer - simply because Linux supports them. It will probably also have an option to use the minix file system for your root file system. > >> It's dead tech, decades ago. It has no advantages over subsequent >> RAID levels, yet significant handicap. > > That's what I thought. But is it remotely practical/useful to use > HDDs for data drives, and one SSD as the parity drive to eliminate > the parity write bottleneck of RAID 4? > > > Chris Murphy-- To unsubscribe from this list: send the line > "unsubscribe linux-raid" in the body of a message to > majordomo@xxxxxxxxxxxxxxx More majordomo info at > http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
