On Tue, Sep 01, 2009 at 01:47:24PM -0400, Vivek Goyal wrote: > On Tue, Sep 01, 2009 at 12:50:11PM -0400, Vivek Goyal wrote: > > Hi Ryo, > > > > I decided to play a bit more with dm-ioband and started doing some > > testing. I am doing a simple two dd threads doing reads and don't seem > > to be gettting the fairness. So thought will ask you what's the issue > > here. Is there an issue with my testing procedure. > > > > I got one 40G SATA drive (no hardware queuing). I have created two > > partitions on that disk /dev/sdd1 and /dev/sdd2 and created two ioband > > devices ioband1 and ioband2 on partitions sdd1 and sdd2 respectively. The > > weights of ioband1 and ioband2 devices are 200 and 100 respectively. > > > > I am assuming that this setup will create two default groups and IO > > going to partition sdd1 should get double the BW of partition sdd2. > > > > But it looks like I am not gettting that behavior. Following is the output > > of "dmsetup table" command. This snapshot has been taken every 2 seconds > > while IO was going on. Column 9 seems to be containing how many sectors > > of IO has been done on a particular io band device and group. Looking at > > the snapshot, it does not look like that ioband1 default group got double > > the BW of ioband2 default group. > > > > Am I doing something wrong here? > > > Hi Ryo, Did you get a chance to look into it? Am I doing something wrong or it is an issue with dm-ioband. Thanks Vivek > I tried another variant of test. This time I also created two additional > groups on ioband1 devices and linked these to cgroups test1 and test2 and > launched two dd threads in two cgroups on device ioband1. There also I > don't seem to be getting the right fairness numbers for cgroup test1 and > test2. > > Script to create ioband devices and additional groups > ----------------------------------------------------- > echo "0 $(blockdev --getsize /dev/sdd1) ioband /dev/sdd1 1 0 0 none" > "weight 0 :200" | dmsetup create ioband1 > echo "0 $(blockdev --getsize /dev/sdd2) ioband /dev/sdd2 1 0 0 none" > "weight 0 :100" | dmsetup create ioband2 > > # Some code to mount and create cgroups. > # Read group id > test1_id=`cat /cgroup/ioband/test1/blkio.id` > test2_id=`cat /cgroup/ioband/test2/blkio.id` > > test1_weight=200 > test2_weight=100 > > dmsetup message ioband1 0 type cgroup > dmsetup message ioband1 0 attach $test1_id > dmsetup message ioband1 0 attach $test2_id > dmsetup message ioband1 0 weight $test1_id:$test1_weight > dmsetup message ioband1 0 weight $test2_id:$test2_weight > > mount /dev/mapper/ioband1 /mnt/sdd1 > mount /dev/mapper/ioband2 /mnt/sdd2 > ----------------------------------------------------------------- > > Following are two dd jobs > ------------------------- > dd if=/mnt/sdd1/testzerofile1 of=/dev/null & > echo $! > /cgroup/ioband/test1/tasks > > dd if=/mnt/sdd1/testzerofile2 of=/dev/null & > echo $! > /cgroup/ioband/test2/tasks > > > Following are "dmsetup status" results every 2 seconds > ====================================================== > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 0 0 0 0 0 0 3 0 0 0 0 0 0 > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 0 0 0 0 0 0 3 0 0 0 0 0 0 > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 689 0 86336 0 0 0 3 650 3 > 81472 0 0 0 > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 1725 0 217024 0 0 0 3 1270 > 11 158912 0 0 0 > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 2690 0 338744 0 0 0 3 1978 > 15 247856 0 0 0 > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 3762 0 474040 0 0 0 3 2583 > 21 323736 0 0 0 > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 4745 0 598064 0 0 0 3 3275 > 27 410392 0 0 0 > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 5737 0 723120 0 0 0 3 3985 > 31 499592 0 0 0 > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 6815 0 859184 0 0 0 3 4594 > 37 575864 0 0 0 > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 2 7823 0 986288 0 0 0 3 5276 > 43 661360 0 0 0 > > "dmsetup table" output > ====================== > ioband2: 0 40355280 ioband 8:50 1 4 192 none weight 768 :100 > ioband1: 0 37768752 ioband 8:49 1 4 192 cgroup weight 768 :200 2:200 3:100 > > Because I am using "weight" policy, I thought that test1 cgroup with id > "2" will issue double the number of requests of cgroup test2 with id "3". > But that does not seem to be happening here. Is there an issue with my > testing method. > > Thanks > Vivek > > > ioband2: 0 40355280 ioband 1 -1 0 0 0 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 0 0 0 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 96 0 11528 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 82 0 9736 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 748 2 93032 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 896 0 112232 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 1326 5 165816 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 1816 0 228312 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 1943 6 243712 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 2692 0 338760 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 2461 10 308576 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 3618 0 455608 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 3118 11 391352 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 4406 0 555032 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 3734 15 468760 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 5273 0 664328 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 4307 17 540784 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 6181 0 778992 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 4930 19 619208 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 7028 0 885728 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 5599 22 703280 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 7815 0 985024 0 0 0 > > > > ioband2: 0 40355280 ioband 1 -1 6586 27 827456 0 0 0 > > ioband1: 0 37768752 ioband 1 -1 8327 0 1049624 0 0 0 > > > > Following are details of my test setup. > > --------------------------------------- > > I took dm-ioband patch version 1.12.3 and applied on 2.6.31-rc6. > > > > Created ioband devices using following command. > > ---------------------------------------------- > > echo "0 $(blockdev --getsize /dev/sdd1) ioband /dev/sdd1 1 0 0 none" > > "weight 0 :200" | dmsetup create ioband1 > > echo "0 $(blockdev --getsize /dev/sdd2) ioband /dev/sdd2 1 0 0 none" > > "weight 0 :100" | dmsetup create ioband2 > > > > mount /dev/mapper/ioband1 /mnt/sdd1 > > mount /dev/mapper/ioband2 /mnt/sdd2 > > > > Started two dd threads > > ====================== > > dd if=/mnt/sdd1/testzerofile1 of=/dev/null & > > dd if=/mnt/sdd2/testzerofile1 of=/dev/null & > > > > Output of dmsetup table command > > ================================ > > ioband2: 0 40355280 ioband 8:50 1 4 192 none weight 768 :100 > > ioband1: 0 37768752 ioband 8:49 1 4 192 none weight 768 :200 > > > > Thanks > > Vivek -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
