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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: p4pn73id9dffaggfdig3ptuok9rugfac X-Rspamd-Queue-Id: 6AB3B16000A X-Rspamd-Server: rspam04 X-Rspam-User: X-HE-Tag: 1718204953-389532 X-HE-Meta: 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 JgNErxrG 3qH4XHq9Gyovw3r2MkSoxHwXLvERZy3KcH6VG2pekyrLheH1Ek7FPbm6NSCO5dZ/Fj5y1Z9LkILRPH3H5zsTiZv3P7M7/JlXy6QHnCYkDIx92PJbStE+D05l33AhYV7avDkuGlFPzYkgs0LL8RRjxsXwRKVFXV7G2n3b8K7oN3CZul8iPHAFvOgsdF1D3hOi0ZIJaP1kdSSW7bVnVf2LcUuLUNd/prTRP90Kuwvtz3wHpZGiS5cQCGa/se9LSasK3Y/RsRHJ2l0ZWsIuNbmgN/8f3ARoHsLKKwIce X-Bogosity: Ham, tests=bogofilter, spamicity=0.015414, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Jun 12, 2024 at 5:47=E2=80=AFAM Usama Arif = wrote: > > With an earlier commit to handle zero-filled pages in swap directly, > and with only 1% of the same-filled pages being non-zero, zswap no > longer needs to handle same-filled pages and can just work on compressed > pages. > > Signed-off-by: Usama Arif > --- > mm/zswap.c | 86 +++++------------------------------------------------- > 1 file changed, 8 insertions(+), 78 deletions(-) > > diff --git a/mm/zswap.c b/mm/zswap.c > index b9b35ef86d9b..ca8df9c99abf 100644 > --- a/mm/zswap.c > +++ b/mm/zswap.c > @@ -44,8 +44,6 @@ > **********************************/ > /* The number of compressed pages currently stored in zswap */ > atomic_t zswap_stored_pages =3D ATOMIC_INIT(0); > -/* The number of same-value filled pages currently stored in zswap */ > -static atomic_t zswap_same_filled_pages =3D ATOMIC_INIT(0); Can we re-introduce this counter somewhere? I have found this counter to be valuable in the past, and would love to keep it. For instance, in a system where a lot of zero-filled pages are reclaimed, we might see an increase in swap usage. Having this counter at hands will allow us to trace the source of the swap usage more easily. I *suppose* you can do elimination work (check zswap usage, check disk swap usage somehow - I'm not sure, etc., etc.), but this would be much more direct and user-friendly. Not *entirely* sure where to expose this though. Seems a bit specific for vmstat. Maybe as a new debugfs directory? This doesn't have to be done in this patch (or this series even) - but please consider this for follow-up work at least :)