Hello,

On Thu, Jun 05, 2025 at 08:31:56AM -0400, Johannes Weiner wrote:

On Wed, Jun 04, 2025 at 08:19:28AM -0400, Johannes Weiner wrote:

quoted

On Fri, May 30, 2025 at 12:31:35PM +0200, Vlastimil Babka wrote:

...

quoted

quoted

I've just read the previous threads about Barry's proposal and if doing this
always isn't feasible, I'm wondering if memcg would be a better interface to
opt-in for this kind of behavior than both prctl or mctl. I think at least
conceptually it fits what memcg is doing? The question is if the
implementation would be feasible, and if android puts apps in separate memcgs...

CCing Tejun.

Cgroups has been trying to resist flag settings like these. The cgroup
tree is a nested hierarchical structure designed for dividing up
system resources. But flag properties don't have natural inheritance
rules. What does it mean if the parent group says one thing and the
child says another? Which one has precedence?

Hence the proposal to make it a per-process property that propagates
through fork() and exec(). This also enables the container usecase (by
setting the flag in the container launching process), without there
being any confusion what the *effective* setting for any given process
in the system is.

+1. If something can work as something which gets inherited through the
process hierarchy, that's usually the better choice than making it a cgroup
property. There isn't much to be gained by making them cgroup properties
especially given that cgroup hierarchy, in most systems at this point, is a
degenerated process hierarchy.

Thanks.

-- 
tejun