On Wed, 28 May 2008, Justin Piszcz wrote:
Hardware: 1. Utilized (6) 400 gigabyte sata hard drives. 2. Everything is on PCI-e (965 chipset & a 2port sata card) Used the following 'optimizations' for all tests. # Set read-ahead. echo "Setting read-ahead to 64 MiB for /dev/md3" blockdev --setra 65536 /dev/md3 # Set stripe-cache_size for RAID5. echo "Setting stripe_cache_size to 16 MiB for /dev/md3" echo 16384 > /sys/block/md3/md/stripe_cache_size # Disable NCQ on all disks. echo "Disabling NCQ on all disks..." for i in $DISKS do echo "Disabling NCQ on $i" echo 1 > /sys/block/"$i"/device/queue_depth done Software: Kernel: 2.6.23.1 x86_64 Filesystem: XFS Mount options: defaults,noatime Results: http://home.comcast.net/~jpiszcz/raid/20080528/raid-levels.html http://home.comcast.net/~jpiszcz/raid/20080528/raid-levels.txt
Why is the Sequential Output (Block) for raid6 165719 and for raid5 only 86797? I would have thought that raid6 was always a bit slower in writting due to having to write double amount of parity data. Holger -- 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
