Hi Andrew, Thank you for the review and comments! On Fri, Nov 1, 2024 at 6:57 AM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > > hm. > > On Thu, 31 Oct 2024 22:45:49 +0000 Kinsey Ho <kinseyho@xxxxxxxxxx> wrote: > > > We noticed high overhead for pages allocated for struct swap_cgroup in > > our fleet. > > This is scanty. Please describe the problem further. In our fleet, we had machines with multiple large swap files configured, and we noticed that we hadn't accounted for the overhead from the pages allocated for struct swap_cgroup. In some cases, we saw a couple GiB of overhead from these pages, so this patchset's goal is to expose this overhead value for easier detection. > And: "the existing use case" is OK with a global counter, but what about > future use cases? > > And: what are the future use cases? As global counting already exists with memmap/memmap_boot pages, the introduction of a generic global counter interface was just to try and aggregate the global counting code when introducing another use case. However, since the value of pages allocated for swap_cgroup can be derived from /proc/swaps, it doesn't seem warranted that a new entry be added to vmstat. We've decided to drop this patchset. Thanks again!
