lkml.org 
[lkml]   [2022]   [Mar]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] zram: Add a huge_idle writeback mode
    On Fri, Mar 18, 2022 at 12:51:14PM -0400, Brian Geffon wrote:
    > On Fri, Mar 18, 2022 at 12:41 PM Minchan Kim <minchan@kernel.org> wrote:
    > >
    > > On Tue, Mar 15, 2022 at 10:22:21AM -0700, Brian Geffon wrote:
    > > > Today it's only possible to write back as a page, idle, or huge.
    > > > A user might want to writeback pages which are huge and idle first
    > > > as these idle pages do not require decompression and make a good
    > > > first pass for writeback.
    > >
    > > Hi Brian,
    > >
    > > I am not sure how much the decompression overhead matter for idle pages
    > > writeback since it's already *very slow* path in zram but I agree that
    > > it would be a good first pass since the memory saving for huge writing
    > > would be cost efficient.
    > >
    > > Just out of curiosity. Do you have real usecase?
    >
    > Hi Minchan,
    > Thank you for taking a look. When we are thinking about writeback
    > we're trying to be very sensitive to our devices storage endurance,
    > for this reason we will have a fairly conservative writeback limit.
    > Given that, we want to make sure we're maximizing what lands on disk
    > while still minimizing the refault time. We could take the approach
    > where we always writeback huge pages but then we may result in very
    > quick refaults which would be a huge waste of time. So idle writeback
    > is a must for us and being able to writeback the pages which have
    > maximum value (huge) would be very useful.

    Thanks for sharing the thought. It really make sense to me and
    would be great if it goes on the description.

    \
     
     \ /
      Last update: 2022-03-18 18:31    [W:2.630 / U:0.296 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site