On Wed, Feb 05, 2025 at 01:08:42PM -0500, Johannes Weiner wrote: > On Wed, Feb 05, 2025 at 12:50:19PM -0500, Hamza Mahfooz wrote: > > Cc: Shakeel Butt <shakeel.butt@xxxxxxxxx> > > > > On 2/5/25 12:48, Hamza Mahfooz wrote: > > > I was just curious as to what the status of the issue described in [1] > > > is. It appears that the last time someone took a stab at it was in [2]. > > If memory serves, the sticking point was whether pages should indeed > be reparented on cgroup death, or whether they could be moved > arbitrarily to other cgroups that are still using them. > > It's a bit unfortunate, because the reparenting patches were tested > and reviewed, and the arbitrary recharging was just an idea that > ttbomk nobody seriously followed up on afterwards. There was an RFC series [1] for the recharging, but all memcg maintainers hated it :P https://lore.kernel.org/lkml/20230720070825.992023-1-yosryahmed@xxxxxxxxxx/ > > We also recently removed the charge moving code from cgroup1, along > with the subtle page access/locking/accounting rules it imposed on the > rest of the MM. I'm doubtful there is much appetite in either camp for > bringing this back. Yeah with the charge moving code gone the case for recharging grows weaker. > > So I would still love to see Muchun's patches merged. They fix a > seemingly universally experienced operational issue in memcg, and we > shouldn't hold it up unless somebody actually posts alternative code. > > Thoughts? Adding Zach and Kinsey who were recently looking into this from the Google side.
