Re: [PATCH v3 6/8] workingset: memcg: sleep when flushing stats in workingset_refault()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, Mar 30, 2023 at 07:17:59PM +0000, Yosry Ahmed <yosryahmed@xxxxxxxxxx> wrote:
> In workingset_refault(), we call
> mem_cgroup_flush_stats_atomic_ratelimited() to read accurate stats
> within an RCU read section and with sleeping disallowed. Move the
> call above the RCU read section to make it non-atomic.
> 
> Flushing is an expensive operation that scales with the number of cpus
> and the number of cgroups in the system, so avoid doing it atomically
> where possible.

I understand why one does not process the whole flushing load in one go
in general.
However, I remember there were reports of workingset_refault() being
sensitive to latencies (hence the ratelimited call was created).

Is there any consideration on impact of this here?
(Or are there other cond_resched() precendents on this path? Should it
be mentioned like in the vmscan (7/8) commit?)

Thanks,
Michal

Attachment: signature.asc
Description: PGP signature


[Index of Archives]     [Linux RAID]     [Linux SCSI]     [Linux ATA RAID]     [IDE]     [Linux Wireless]     [Linux Kernel]     [ATH6KL]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Device Mapper]

  Powered by Linux