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) best regards Hong Zhiguo -- 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