On Tuesday September 11, brederlo@xxxxxxxxxxxxxxxxxxxxxxxxxxx wrote: > > I found that near copies behave like raid1, offset copies are slower > in both reading and writing (beats me why) and far copies are slightly > faster than near copies in write and twice as fast in read. All for > sequential read/write. For random writes far copies should be slower > to write. I would expect read performance on an 'offset' layout to be significantly affected by the chunk size. You probably want the chunk size to be about 4 times the cylinder size. The ideal would be exactly the cylinder size, and exactly aligned to cylinders. But as cylinder sizes change across the device, this is not possible. Unfortunately I don't know how big cylinders are. I suspect if you hunt through the docs for the device you might find out. NeilBrown - 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
