RE: [PATCH v3 12/13] mm: Add sysctl vm.compress-batching switch for compress batching during swapout.

Sridhar, Kanchana P
2024-11-09T01:05:14Z

> -----Original Message-----
> From: Yosry Ahmed <yosryahmed@google.com>
> Sent: Friday, November 8, 2024 12:24 PM
> To: Johannes Weiner <hannes@cmpxchg.org>
> Cc: Sridhar, Kanchana P <kanchana.p.sridhar@intel.com>; linux-
> kernel@vger.kernel.org; linux-mm@kvack.org; nphamcs@gmail.com;
> chengming.zhou@linux.dev; usamaarif642@gmail.com;
> ryan.roberts@arm.com; Huang, Ying <ying.huang@intel.com>;
> 21cnbao@gmail.com; akpm@linux-foundation.org; linux-
> crypto@vger.kernel.org; herbert@gondor.apana.org.au;
> davem@davemloft.net; clabbe@baylibre.com; ardb@kernel.org;
> ebiggers@google.com; surenb@google.com; Accardi, Kristen C
> <kristen.c.accardi@intel.com>; zanussi@kernel.org; Feghali, Wajdi K
> <wajdi.k.feghali@intel.com>; Gopal, Vinodh <vinodh.gopal@intel.com>
> Subject: Re: [PATCH v3 12/13] mm: Add sysctl vm.compress-batching switch
> for compress batching during swapout.
>
> On Thu, Nov 7, 2024 at 9:34 AM Johannes Weiner <hannes@cmpxchg.org>
> wrote:
> >
> > On Wed, Nov 06, 2024 at 11:21:04AM -0800, Kanchana P Sridhar wrote:
> > > The sysctl vm.compress-batching parameter is 0 by default. If the platform
> > > has Intel IAA, the user can run experiments with IAA compress batching of
> > > large folios in zswap_store() as follows:
> > >
> > > sysctl vm.compress-batching=1
> > > echo deflate-iaa > /sys/module/zswap/parameters/compressor
> >
> > A sysctl seems uncalled for. Can't the batching code be gated on
> > deflate-iaa being the compressor? It can still be generalized later if
> > another compressor is shown to benefit from batching.
>
> +1

Thanks Yosry & Johannes. Will proceed as suggested.

Thanks,
Kanchana