Hello Tejun & cgroup, I encountered several questions playing with cgroup that I really hope to get your answers. I referred to this LWN article for writeback support https://lwn.net/Articles/628631/ and did following steps: - clone git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git and checkout branch review-cgroup-writeback-20150106 - compile and boot with option cgroup__DEVEL__legacy_files_on_dfl - umount all subsys then do mount -t cgroup -o __DEVEL__sane_behavior cgroup /sys/fs/cgroup/ - found blkio memory already in cgroup.subtree_control as default - created new group /sys/fs/cgroup/bash, and play with IO throttling both with iops and wbps, both on my sda ext4 and sdb ext2 Then I found it's not working... I realized the article states only ext2 was adapted but it's not working either : ) Then I turned to this page https://kernelnewbies.org/Linux_4.2#head-8f54d7519fca6b2504f5f26290f46081d6cb6927 saying Linux-4.2 has writeback support. I did similar steps as above except cloning from linux-stable.git, and it's not working either. I noticed this code is largely different from the review-cgroup-writeback-20150106 branch based on 3.19.0 (e.g., dirty_context). However Linux-4.3.3 and Linux-4.10.0 really works, except that control files have changed in 4.3.3 and we can directly use cgroup2 in 4.10.0. Is it because I did something wrong or missed anything? As I find many branches exist in kernel/git/tj/cgroup.tj, it would be great if you could help explain the roles of the different branches and how the repo works in general. Especially, I want to know the first repo branch/linux release that has writeback support so it's easier to learn how it's built up step by step from the commit log. Thank you very much! Benlong -- 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
