Hi David, > My current state is that I've got theory worked out and written up - > not just for triple parity, but for more parities as well. For some > of it, I've got Python code to test and verify the maths. It turns > out that triple parity can work well - but for quad parity the limit > is 21 data disks (using generators 2, 4, and 8), or up to 33 (using > for example 0x07, 0x35 and 0x8b as generators). Realistically, I > think triple parity is the limit for practical implementations. Why is that? An RS code (255,251) should be possible, like it is a (255,223). What's the limitation? I'm sure there is even a "RAID-96", which is (96,64). My wild guess would be that the generators must be chosen in some way. Have you had a look at the "par2" code? That seems to be capable of doing a parametric RS, even if in 16bit words. bye, -- piergiorgio -- 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
