On 2022/5/27 下午4:48, Tejun Heo wrote:
On Fri, May 27, 2022 at 10:39:18AM +0800, Hongchen Zhang wrote:
when remove a cgroup dir, make sure all the csses associated which
the cgroup are all offlined,so that we will be sure that the resources
allocated by the csses are all freed when rmdir exit successfully.
Offlining doesn't guarantee that resources are freed and there's no definite
time limit on how long it'd take to free all resources. e.g. for memcg, if
there isn't sufficient memory pressure, its page cache can remain
indefinitely. Is there something practical you're trying to achieve?
Thanks.
Hi Tejun,
When I test the LTP's memcg_test_3 testcase at 8 Node server,I get
the -ENOMEM error,which caused by no avaliable idr found in mem_cgroup_idr.
the reason is the use of idr in mem_cgroup_idr is too fast than the
free.In the specific case,the idr is used and freed cyclically,so when
we rmdir one cgroup dir, we can synchronize the idr free through wating
for the memcg css offlined,and then we can use it the next cycle.
Thanks.
