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J . Mercier" , Martin Liu , Minchan Kim , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, Jul 8, 2026 at 12:54=E2=80=AFPM Shakeel Butt wrote: > > What's so special about proactive reclaim? Why the same situation can not= happen > for global or memcg reclaim? > The target batch size of the global/memcg reclaim is typically very small -- usually SWAP_CLUSTER_MAX (32 pages), allowing the task to yield or check signals between attempts. Furthermore, kswapd is a kernel thread designed to be freezable, it explicitly checks kthread_freezable_should_stop() in the main loop. In contrast, the target batch size in proactive reclaim is user-defined and can be extremely large. Without signal checks in the inner loops, the task may continue scanning and evicting pages for seconds at a time.