On Tue, Oct 15 2013, Hong zhi guo wrote: > Hi, Tejun, > > I did the test for 3 levels hierarchy. It works. > > Preparation > ============ > 1) mount subsys blkio with "__DEVEL__sane_behavior" > 2) Create 3 levels of directories under the blkio mount point: > mkdir 1 > mkdir 1/2 > mkdir 1/2/3 > 3) start 3 bash sessions, write their PIDs into: > 1/cgroup.procs > 1/2/cgroup.procs > 1/2/3/cgroup.procs > 4) prepare 3 10MB files on sdb(ext4 fs) > > Note: in below hierarchy graph: > "[50k]" means configured value for read_bps_device is 50kB/s > "(50k)" means bandwidth reported by dd is 50kB/s > > Test A: 1 process throttled by ancestor group > ============================================= > Hierarchy set-up: > (echo "8:16 204800" > 1/blkio.throttle.read_bps_device) > 1 [200k] > `-- 2 [-] > `-- 3 [-] > > dd within group 3: > (drop cache then: dd if=10M-file-3 of=/dev/null) > Result: > 206kB/s (I did same test without the token-bucket patch, The > result is 205kB/s) > > dd within group 2: > (drop cache then: dd if=10M-file-2 of=/dev/null) > Result: > 205kB/s > > > Test B: 3 processes in 3 levels of hierarchy > ============================================= > Hierarchy set-up: > echo "8:16 204800" > 1/blkio.throttle.read_bps_device > echo "8:16 102400" > 1/2/blkio.throttle.read_bps_device > echo "8:16 51200" > 1/2/3/blkio.throttle.read_bps_device > 1 [200k] > `-- 2 [100k] > `-- 3 [50k] > start 3 dd processes from 3 bash sessions > (dd if=10M-file-x of=/dev/null) > Result: > 1 (103k) > `-- 2 (51.9k) > `-- 3 (51.4k) Thanks for doing this testing, and the work to move to a token based system. It makes a lot of sense. I've been investigating a token based scheduler for blk-mq as well, since that could feasibly be made to scale as well. -- Jens Axboe -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html