Re: [PATCH v2 1/2] hugetlb: memcg: account hugetlb-backed memory in memory controller

From: Johannes Weiner
Date: Mon Oct 02 2023 - 12:21:41 EST


On Mon, Oct 02, 2023 at 03:43:19PM +0200, Michal Hocko wrote:
> We should also consider the global control for this functionality. I am
> especially worried about setups where a mixed bag of workloads
> (containers) is executed. While some of them will be ready for the new
> accounting mode many will leave in their own world without ever being
> modified. How do we deal with that situation?

It's possible to add more localized control on top of the global flag
should this come up. But this seems like a new and honestly pretty
hypothetical usecase, given the host-level coordination already
involved in real-world hugetlb setups.

The same could be said about other mount options, such as nsdelegate,
memory_localevents, and memory_recursiveprot. Those you'd expect to
have a much broader audience, and nobody has asked for mixed use.

Let's cross this bridge not when but if we have to.