Re: [PATCH v4 2/4] zram: implement deduplication in zram

From: Minchan Kim
Date: Wed Apr 26 2017 - 03:40:02 EST


On Wed, Apr 26, 2017 at 04:21:47PM +0900, Sergey Senozhatsky wrote:
> On (04/26/17 15:59), Joonsoo Kim wrote:
> [..]
> > > Actually, I found it for the last review cycle but didn't say that
> > > intentionally. Because it is also odd to me that pages_stored isn't
> > > increased for same_pages so I thought we can fix it all.
> > >
> > > I mean:
> > >
> > > * normal page
> > > inc pages_stored
> > > inc compr_data_size
> > > * same_page
> > > inc pages_stored
> > > inc same_pages
> > > * dedup_page
> > > inc pages_stored
> > > inc dup_data_size
> > >
> > > IOW, pages_stored should be increased for every write IO.
> > > But the concern is we have said in zram.txt
> > >
> > > orig_data_size uncompressed size of data stored in this disk.
> > > This excludes same-element-filled pages (same_pages) since
> > > no memory is allocated for them.
> > >
> > > So, we might be too late. :-(
> > > What do you think about it?
> > > If anyone doesn't have any objection, I want to correct it all.
> >
> > I have no objection.
> > If so, do I need to postpone this patchset until others are fixed?
>
> this probably will mess with your series a lot. so I don't mind if you or
> Minchan will send stats-fixup patch after the dedup series. may be/preferably
> as the last patch in the series. but if you or Minchan want to fix stats
> first, then I wouldn't mind either. I just don't make a big deal out of those
> stats, a bunch of fun to know numbers. my 5cents.

After Andrew takes dedup patchset, I will fix it later.
Thanks.