On 2/19/2013 4:46 PM, Chris Murphy wrote: > 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? I don't see how. The SSD dedicated to parity must have the same capacity as the HDDs. The largest non PCIe monster SDDs are right at 1TB and the cheapest of those is ~$1000. If the goal is to do an end run around slow parity writes of RAID4, then RAID10/0+1/etc with HDDs gives a lot more capacity and performance for the same or less money. Hybrid RAID4 setup: 2TB net capacity Mushkin Enhanced 2.5" 960GB = $1000 2x Hitachi 1TB 7.2K 2.5" = $ 200 $1200 RAID10 setup: 6TB net capacity 12x Hitachi 1TB 7.2K 2.5" = $1200 The RAID10 setup has 3x write performance and capacity for the same money, albeit with more power draw and more ports required. -- Stan -- 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
