Re: [PATCH v2 0/4] mm/zswap: Implement per-cgroup proactive writeback

[Yosry Ahmed]

On Tue, May 26, 2026 at 4:56 AM Hao Jia <jiahao.kernel@xxxxxxxxx> wrote:
>
>
>
> On 2026/5/26 03:24, Andrew Morton wrote:
> > On Mon, 25 May 2026 20:22:38 +0800 Hao Jia <jiahao.kernel@xxxxxxxxx> wrote:
> >
> >> Zswap currently writes back pages to backing swap reactively, triggered
> >> either by the shrinker or by the pool reaching its size limit. Although
> >> proactive memory reclaim can automatically write back a portion of zswap
> >> pages via the shrinker, it cannot explicitly control the amount of
> >> writeback for a specific memory cgroup. Moreover, proactive memory reclaim
> >> may not always be triggered during a steady state.
> >>
> >> In certain scenarios, it is desirable to trigger writeback in advance to
> >> free up memory. For example, users may want to prepare for an upcoming
> >> memory-intensive workload by flushing cold memory to the backing storage
> >> when the system is relatively idle.
> >>
> >> This patch series introduces a "zswap_writeback_only" key to memory.reclaim
> >> cgroup interface, allowing users to proactively write back cold compressed
> >> pages from zswap to the backing swap device. When specified, this key
> >> bypasses standard memory reclaim and exclusively performs proactive zswap
> >> writeback up to the requested budget. If omitted, the default reclaim
> >> behavior remains unchanged.
> >
> > Thanks.  AI review found a few things to complain about, one of them
> > described as "preexisting".
> >
>
> Thanks Andrew.  I have replied to the AI's review comments in a separate
> email and posted v3.
> https://lore.kernel.org/all/20260526114601.67041-1-jiahao.kernel@xxxxxxxxx

Generally speaking, please give time for reviewers to take a look
before sending a new version. Less than a day is usually too fast
(unless you're iterating super fast with the reviewers). Review
feedback does not have to be addressed immediately, usually wait for a
bit to collect as much feedback as possible before spinning a new
version.

I will take a look at v3 soon, thank you.