> This mishmash combo of drives, including two WD Green Advanced Format > drives, is likely the cause of the horrible write performance. You're > assembling the array from partitions. first of all: sorry but my english is not good :-( In many howto I read: "create a partition of disk and change it to "fd" code: linux raid autodetect" Now I re-done whole raid (I already have a backup) I have to create a partition on sigle disk? or remove any partition and stop? > The partitions on the WD20EARS > drives are undoubtedly not 4KB sector aligned, causing excessive > read-modify-write cycles. See: > http://en.wikipedia.org/wiki/Advanced_Format > Repartition the Green drives with proper alignment. If you still have > issues we'll go from there. Note: Having 3 dissimilar drives in an > array is never going to be an optimally performing solution. Now I re-create a new raid system with 6 disks (everyone 2Tb wd) How do about 4Kb sector align? thanks! Pol -- 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
