It looks like a bug on cgroup writeback. Is this a regression or
consistent issue? If it's a regression, you may could do bisect to
find out the buggy commit.
On Tue, Apr 19, 2016 at 3:19 PM, zhong jiang <zhongji...@huawei.com> wrote:
> cgroup writeback support the filesystem both ext4 and ext2.
> but, it appears to be not work when I test the function in the ext4.
> The example is as follows:
> echo "8:0 1048576" > blkio.throttle.write_bps_device
> echo $$ > cgroup.procs
> dd if=/dev/zero of=/test.c bs=1M count=10240
> 10240+0 records in
> 10240+0 records out
> 10737418240 bytes (11 GB) copied, 49.8796 s, 215 MB/s
>
> Furthering test find that the ratelimit will be limited if it write data
> to disk directly. Additionly, The read ratelimit is limited whther it go
> through
> the page cache or not.
>
> The kernel version is 4.6 I have tested, And the corresponding files
> in the attachment
--
Thanks
Alex
