On Tue, Jul 16, 2024 at 9:48 AM Michal Hocko <mhocko@xxxxxxxx> wrote: > > On Mon 15-07-24 16:36:26, David Finkel wrote: > > Other mechanisms for querying the peak memory usage of either a process > > or v1 memory cgroup allow for resetting the high watermark. Restore > > parity with those mechanisms. > > > > For example: > > - Any write to memory.max_usage_in_bytes in a cgroup v1 mount resets > > the high watermark. > > - writing "5" to the clear_refs pseudo-file in a processes's proc > > directory resets the peak RSS. > > > > This change copies the cgroup v1 behavior so any write to the > > memory.peak and memory.swap.peak pseudo-files reset the high watermark > > to the current usage. > > > > This behavior is particularly useful for work scheduling systems that > > need to track memory usage of worker processes/cgroups per-work-item. > > Since memory can't be squeezed like CPU can (the OOM-killer has > > opinions), these systems need to track the peak memory usage to compute > > system/container fullness when binpacking workitems. > > > > Signed-off-by: David Finkel <davidf@xxxxxxxxx> > > As mentioned down the email thread, I consider usefulness of peak value > rather limited. It is misleading when memory is reclaimed. But > fundamentally I do not oppose to unifying the write behavior to reset > values. > > The chnagelog could use some of the clarifications down the thread. Sure, I can spend some time rewording the changelog this afternoon, and remail it. in a few hours. > > Acked-by: Michal Hocko <mhocko@xxxxxxxx> > Thank you! > -- > Michal Hocko > SUSE Labs -- David Finkel Senior Principal Software Engineer, Core Services
