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Subject: Re: [PATCH] memcg: allow exiting tasks to write back data to swap
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To: Balbir Singh <balbirs@nvidia.com>, Johannes Weiner <hannes@cmpxchg.org>
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Date: Thu, 12 Dec 2024 09:03:48 -0500
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On Thu, 2024-12-12 at 14:25 +1100, Balbir Singh wrote:
>=20
> I was asking about this change (this patch), I know that the return
> true will help avoid the PAGE_ACTIVATE path, but I am not sure why
> this function will return false if CONFIG_ZSWAP is enabled (unless
> zswap_writeback is turned off in one of the groups)
>=20
Some workloads are fine with incurring the latency
from zswap, but do not want the latency of actual
block device backed swap.

Having zswap enabled, with writeback disabled, has
been beneficial to a number of workloads.

--=20
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