From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B1436125A0 for ; Sat, 11 Jul 2026 00:39:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783730392; cv=none; b=FE9almWrO/oAOFEUbAy2r7yfP1q2OzMAc++a3I7/cj3zRhp2/fHnUQylb2r+YC2Cu2hD3f5GRB9OVp1lxRu3N2JjtDgmYjrVbR60vrMxJGnA4yH7i3RaV6ZdVj63IsAE5K1dfTsTfRBGsmqUWLPjdGIJr4NPyTnUxIHrHzJd2Ow= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783730392; c=relaxed/simple; bh=shIObB1AwHaxhOd9cCbrOh3aZBhbPgd7vflTMkKwmuo=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=cb6qD0uWHSbAy45BBzAFZ7TOvq3Z7EucnEsYz9zB/TM+v7X3XVP6vPe/jJK9MMEYeGoNt9dUJP++QvG1yKxJYvYazwRJD5mOp+n7NjFa1z4VJg155vvkdMeIy+Wc4dLCwQMRBqjcLRWONpg6MJ9giutkjcoDL1oGVL6p5sE2Hi0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=bl2l1g03; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="bl2l1g03" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BBC921F00A3A; Sat, 11 Jul 2026 00:39:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1783730391; bh=GqJr7yUpkIPQV2kdt+vlH1KgFs6WG1ulCiswcCMvBZU=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=bl2l1g03sHnPglMFtsXroyHuhGQfWxq4H3TZ2lhDMJnkym6Hb5v/atJgAFDdXaZno wx8045d3zTj2VuxcC5HkRszRmiL+e4S5XsQReSSTD/cUontA3kENoPMsoqmoCy7hLK 8z6JsX5TsoplWFsOTh+ACoq7GqW1DlVOV+s/RT8I= Date: Fri, 10 Jul 2026 17:39:50 -0700 From: Andrew Morton To: Altan Hacigumus Cc: David Hildenbrand , Johannes Weiner , Kairui Song , Qi Zheng , Shakeel Butt , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jiayuan Chen , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/vmscan: clear hopeless kswapd when global direct reclaim makes progress Message-Id: <20260710173950.cc42b1b9c8d25fb02b29cf00@linux-foundation.org> In-Reply-To: References: <20260710024429.70923-1-ahacigu.linux@gmail.com> <20260709202247.8cf6d7ab840f3a45c7eac409@linux-foundation.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 9 Jul 2026 21:04:20 -0700 Altan Hacigumus wrote: > > Does this change have any user-visible effect? If so, please describe > > in elaborate detail. > > > > Yes, the effect is visible on systems where a db workload mlocks 80%+ > of memory and the remaining memory is under continuous pressure: > allocations stall long enough that ordinary tasks (e.g. ssh) become > slow or unresponsive. > > > If not then that's OK - we make such changes all the time, but they're > > less fun. > > > This was introduced by commit dc9fe9b7056a; for long before it, any > reclaim progress revived kswapd. Now only a balanced node clears the > hopeless state, which is too restrictive for global direct reclaim. Great, thanks. Please get this info into the changelog and maintain it! I'll park the patch for a week or so, give reviewers time to catch up.