hi neil i think i ended the first version of read_balance options could you check? i need more help with sysfs (i put the time based configuration in only one file, sysfs filosophy shows that's wrong, but i don't know how to make it per mirror... :/) another thing, can i get a per mirror i/o list? for example mirror 1, what's the current i/o queue? how many writes in queue? how many read? what's the min() and max() sector of queue? the source is kernel 2.6.37 based, can be found here: http://www.spadim.com.br/raid1/ using: /sys/block/md0/md/read_balance_mode you can select read mode near_head = current raid1 read_balance round_robin = a patch of Roy Keene (linux-raid at rkeene.org) stripe = make a division (stripe) of read time_based = select the best disk based on distance (current head position sector - read sector)*head_distance_rate + read_sectors * read_sectors_rate + queue_io_time (this i need to implement) for stripe there's a file to configure it /sys/block/md0/md/read_balance_stripe_shift the selected disk for stripe is: ((current_sector >> stripe_shift) & 0xeff) % raid_disks for time based there's another file configuration: /sys/block/md0/md/read_balance_time_config if you use cat you get all information about mirror you should use: echo "x y z w" > read_Balance_time_config x = raid mirror id (index of conf->mirrors[]) y = head_distance_rate z = read_sectors_rate w = write_sectors_rate how to use yzw: if you use two disks: first: 10ms of access time second: 2ms of acess time for disk1: y =1 for disk2: y =5 first: 10mb/s read rate (test with dd of=/dev/zero if=/dev/sda) second: 20mb/s read rate for disk1: z = 2 for disk2: z = 1 first: 20mb/s write rate (test with dd if=/dev/zero of=/dev/sda) second: 10mb/s write rate for disk1: w = 1 for disk2: w = 2 that's it :) the timebased run only once (at begin of read_balance) if error (goto retry) it will use near_head, but not change the read_balance_mode variable it's time to test, and benchmark i need a help with bio queue if you could help me :) thanks =) -- Roberto Spadim Spadim Technology / SPAEmpresarial -- 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
