Re: [RFC PATCH 5/9] mm: zswap: remove zswap_same_filled_pages_enabled

From: Nhat Pham
Date: Tue Mar 26 2024 - 18:01:37 EST


On Mon, Mar 25, 2024 at 4:50 PM Yosry Ahmed <yosryahmed@xxxxxxxxxx> wrote:
>
> There is no logical reason to refuse storing same-filled pages more
> efficiently and opt for compression. Remove the userspace knob.
>

Agree. Absolutely no idea why we have this knob in the first place -
if you have cycles to compress, you probably have some extra cycles to
check same-filled page state? And that is the only cost I can think of
- it wins on probably all other aspects: memory usage,
"decompression", no need to write back these pages etc.

Any actual zswap user who has data or counter-use case should chime
in, but FWIW, my vote is:
Reviewed-by: Nhat Pham <nphamcs@xxxxxxxxx>