> Note also that you're doing 4KB random writes against RAID5. This is > going to generate substantial RMW cycles. The Intel X25-M G2 is not a > speed daemon. Its published max 4KB IOPS throughput is for purely > random writes, not the read+write pattern created by parity RMW. So > while your random read should get a nice jump with this test, your > random write may not improve as much. The limitation here is a function > of the SSD controller on the X25-M G2, not md/RAID5. If you test 5 > drives in md/RAID0 you'll see a bump in random write IOPS. > It seems so. I let fio run a bit longer and in each settings the ssd- performance decreased after few minutes. While mpstat still showed ~100% ssd- utilization. -- 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
