On 03/09/2012 03:20 PM, Jeff Liu wrote:
Hello, Disk quota feature has been asked at LXC list from time to time. Given that the project quota has already implemented in XFS for a long time, and it was also in progress for EXT4. So the major idea is to assign one or more project IDs(or tree ID?) to container, but leaving quota setup via cgroup config files, so all the tasks running at container could have project quota constraints applied. I'd like to post an initial patch sets here, the stupid implements is very simple and even crash me in some cases, sorry! But I would like to submit it to get more feedback to make sure I am going down the right road. :) Let me introduce it now. 1. Setup project quota on XFS(enabled pquota) firstly. For example, the "project100" is configured on "/xfs/quota_test" directory. $ cat /etc/projects 100:/xfs/quota_test $ cat /etc/projid project100:100 $ sudo xfs_quota -x -c 'report -p' Project quota on /xfs (/dev/sda7) Blocks Project ID Used Soft Hard Warn/Grace ---------- -------------------------------------------------- project100 0 0 0 00 [--------] 2. Mount cgroup on /cgroup. cgroup on /cgroup type cgroup (rw) After that, there will have a couple of quota.XXXX files presented at /cgroup. $ ls -l /cgroup/quota.* --w------- 1 root root 0 Mar 9 18:27 /cgroup/quota.activate --w------- 1 root root 0 Mar 9 18:27 /cgroup/quota.add_project -r--r--r-- 1 root root 0 Mar 9 18:27 /cgroup/quota.all --w------- 1 root root 0 Mar 9 18:27 /cgroup/quota.block_limit_in_bytes --w------- 1 root root 0 Mar 9 18:27 /cgroup/quota.deactivate --w------- 1 root root 0 Mar 9 18:27 /cgroup/quota.inode_limit -r--r--r-- 1 root root 0 Mar 9 18:27 /cgroup/quota.projects --w------- 1 root root 0 Mar 9 18:27 /cgroup/quota.remove_project --w------- 1 root root 0 Mar 9 18:27 /cgroup/quota.reset_block_limit_in_bytes --w------- 1 root root 0 Mar 9 18:27 /cgroup/quota.reset_inode_limit 3. To assign a project ID to container, just echo it to quota.add_project as: echo "project100:100"> /cgroup/quota.add_project To get a short list of the current projects assigned to container, user can check quota.projects, # cat /cgroup/quota.projects Project ID (project100:100) status: off The totally quota info can be check against quota.all, it will show something like below: # cat /cgroup/quota.all Project ID (project100:100) status: off block_soft_limit 9223372036854775807 block_hard_limit 9223372036854775807 block_max_usage 0 block_usage 0 inode_soft_limit 9223372036854775807 inode_hard_limit 9223372036854775807 inode_max_usage 0 inode_usage 0 Note that about "status: off", by default, a new assigned project will in OFF state, user could turn it on by echo the project ID to quota.activate as below: # echo 100> /cgroup/quota.activate # cat /cgroup/quota.all Project ID (project100:100) status: on *now status changed.* block_soft_limit 9223372036854775807 block_hard_limit 9223372036854775807 block_max_usage 0 block_usage 0 inode_soft_limit 9223372036854775807 inode_hard_limit 9223372036854775807 inode_max_usage 0 inode_usage 0 But it will do nothing since without quota setup. 4. To configure quota via cgroup, user need to interact with quota.inode_limit and quota.block_limit_in_bytes. For now, I only add a simple inode quota check to XFS, it looks something like below: # echo "100 2:4">> /cgroup/quota.inode_limit # cat /cgroup/quota.all Project ID (project100:100) status: on block_soft_limit 9223372036854775807 block_hard_limit 9223372036854775807 block_max_usage 0 block_usage 0 inode_soft_limit 2 inode_hard_limit 4 inode_max_usage 0 inode_usage 0 # for ((i=0; i< 6; i++)); do touch xfs/quota_test/test.$i; done Project ID (project100:100) status: on block_soft_limit 9223372036854775807 block_hard_limit 9223372036854775807 block_max_usage 0 block_usage 0 inode_soft_limit 2 inode_hard_limit 4 inode_max_usage 4 inode_usage 4 Sorry again, above steps crashed me sometimes for now, it works just for demo purpose. :) Any criticism and suggestions are welcome!
I have mixed feelings about this. The feature is obviously welcome, but I am not sure if the approach you took is the best one... I'll go through the patches now, and hopefully will
have a better opinion by the end =) -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html