On 11.10.21 11:28, Michal Hocko wrote:
On Fri 08-10-21 10:17:50, David Hildenbrand wrote:
On 08.10.21 08:39, ultrachin@xxxxxxx wrote:
From: chen xiaoguang <xiaoggchen@xxxxxxxxxxx>
The exit time is long when program allocated big memory and
the most time consuming part is free memory which takes 99.9%
of the total exit time. By using async free we can save 25% of
exit time.
Signed-off-by: chen xiaoguang <xiaoggchen@xxxxxxxxxxx>
Signed-off-by: zeng jingxiang <linuszeng@xxxxxxxxxxx>
Signed-off-by: lu yihui <yihuilu@xxxxxxxxxxx>
I recently discussed with Claudio if it would be possible to tear down the
process MM deferred, because for some use cases (secure/encrypted
virtualization, very large mmaps) tearing down the page tables is already
the much more expensive operation.
There is mmdrop_async(), and I wondered if one could reuse that concept when
tearing down a process -- I didn't look into feasibility, however, so it's
just some very rough idea.
This is not a new problem. Large process tear down can take ages. The
primary road block has been accounting. This lot of work has to be
accounted to the proper domain (e.g. cpu cgroup).
In general, yes. For some setups where admins don't care about that
accounting (e.g., enabled via some magic toggle for large VMs), I guess
this accounting isn't the major roadblock, correct?
--
Thanks,
David / dhildenb
