From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f54.google.com (mail-wm1-f54.google.com [209.85.128.54]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 42E933AA4F3 for ; Thu, 19 Mar 2026 08:35:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.54 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773909343; cv=none; b=icNvcgfjxhNBpQk+U/2xFH+NR9qed6y+/rgJXpgoxQgzi+zwWWji914QBK3oK/JRhLyoq3KXw87cr5drDSyTijiumz0TyBTriEKC2lkHbX1AHheXbkmVkE+wvibKN4LsMSfXKHXZfeKhMR36ITvSE7JDk2FAcXoAntzXZBlW0V4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773909343; c=relaxed/simple; bh=brlHYeYbANutdqbkUniu7UEfgllAoV3PFIv7GsJEY9I=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=K7RmQKv9sjDUkV9v3mY3P6lbQ1ie3ATRX+9DFH/KTKoBGuaLCKrF1xOgYDvd2lC2NbaXHXS0pbUei0SMEwW5PhyH4qr7v6CusdWB9nMgForCI5WkKjGp7adCABFwmjLF5dbWkYs8WbeG2jD22/X54CxlwnCHo5QXgT9jXOmMrYE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b=SFeFoZPP; arc=none smtp.client-ip=209.85.128.54 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b="SFeFoZPP" Received: by mail-wm1-f54.google.com with SMTP id 5b1f17b1804b1-486fb439299so2904865e9.0 for ; Thu, 19 Mar 2026 01:35:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1773909340; x=1774514140; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=31Icc71U+5J9ABaJwtmAWm2GzoqXy8yAq2rOU0PBch0=; b=SFeFoZPPXZsfcj1O71ulrL7ungQBhtUDIaVQMq++lmUuN3NbawcLM5JWbtOsGWrGrx RVfIiKhAGxhsZnnLBAMTgkhFRN44dq1VzFdbaB6drKLqCTVPQqgym1HI8kjw2c/GKY11 BEHUMiOwMgJGSRAx7GOvaO3eiNKv5rE2YuUoBA/67SnbyHKbqv4fQoNnomVS6A7k8nzS 3r2su98kKgR8TmahALIzIcXR1Zed0E/QgOogF/vNMnuZG3Az6ReG0Bbq8N0MAxlTFMdO u4UiuRdr9Bvh7elcxOP3hbgnk5znNDaJ7EAiSBagmiOXZxTVSMLF54tXWgxpwk6dfcSr 13kg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1773909340; x=1774514140; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=31Icc71U+5J9ABaJwtmAWm2GzoqXy8yAq2rOU0PBch0=; b=ZxsJXtd4lUsTiPUE7evUvkmYcZWoqtmFzKOyNhId0U+rQYuj3OhgDmnkkza50imu/C 284ujCgzw6vwQncHHROulB4p+0kwC5toDnBmlvkarE9rPbXnlM/AIiKixnnCZzlVkXZW eTAmT/KOnRlXAzl/DJA4fL6cDNTy+qrHgXf6O3fDU3ZCpghiW63bR8O85Xtvk5axsZto 2toxI0cZPyKTi+eBVCZ60MkmYTjRTQ3PV5SEAvtNMLDxs6DwsxycktXtFj7f2whCEmr5 GC8L7nidCUe+17B/+74kfuvdl8VVCoVPa/AqwHgwTft8MiVp5dgpctlG3BQMzgjh3nEB K8XQ== X-Forwarded-Encrypted: i=1; AJvYcCUiVH9e+1yXlsmsx++JpWpV4nk9ie6QgCdZWeDzp9q1week5laTX4k66ZRkMzUs+GaVmweBh54f@vger.kernel.org X-Gm-Message-State: AOJu0YxgwZYTNDBGaK2Bpp4JV7hhYcEiC97vLNRFLVX5pPXKqSSoAj2x PmF93TuBgnGZRAe1Sh94DHn0Y0pn3UJF2XRH+EfCPDg4OSaXeLISAKTDzz72vMxKI4I= X-Gm-Gg: ATEYQzzyMa4ZCrELr1rf9sRwszY3D5GlbIc7MnDF0H0LWccQxoOXrzqHBFYs5usvKgI hgIjhPoP5wcjstJi6wrI0El0HGCrR7StdDtfMNGNVjiAJfQ6d4ybJq1xk72CtTrmSN0tU7Lf1WQ TOYigkNBytN8pg2+oli/rYgFx+G2zCHDJDJw99GYEJt/IhYimard1FyMd3fLRSkIMQYDucCCAVb pHH3EiP6Qw5iwSHkzBNSMNyv/GoHkMXxFWGzrUkOa0m5E43HkWfa8IrW7cycXp4a0enYLCDxRT6 8M6ZhEPAYQTjiJZj9hj3cf1BoVRqnf4okj4GC9/3tg4PvsNLAFqjSNt9D7Gm6O+24ZaYuwc5MtZ 61Lq/dHeNsLpF5MkmqBFfuol4E2pC/+Rt9/akWf834/BqsD9Sz22D28AI3bbWhEXg+AUr3SbRts PNk1rFbNZr7oDRJ6lt7zRsrruvidKftM9KvA== X-Received: by 2002:a05:600c:8483:b0:485:3f72:3230 with SMTP id 5b1f17b1804b1-486f4430051mr100136185e9.15.1773909340450; Thu, 19 Mar 2026 01:35:40 -0700 (PDT) Received: from localhost (109-81-88-11.rct.o2.cz. [109.81.88.11]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-486f8c292e2sm48894715e9.2.2026.03.19.01.35.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 19 Mar 2026 01:35:40 -0700 (PDT) Date: Thu, 19 Mar 2026 09:35:38 +0100 From: Michal Hocko To: Shakeel Butt Cc: Daniil Tatianin , Andrew Morton , Johannes Weiner , Roman Gushchin , Muchun Song , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Axel Rasmussen , Yuanchu Xie , Wei Xu , Brendan Jackman , Zi Yan , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, yc-core@yandex-team.ru Subject: Re: [PATCH] mm: add memory.compact_unevictable_allowed cgroup attribute Message-ID: References: <3db237d0-1ee8-44b7-a356-f3015173f7c2@yandex-team.ru> <7ca9876c-f3fa-441c-9a21-ae0ee5523318@yandex-team.ru> <73322279-c6f8-4319-827b-938c20c96b9b@yandex-team.ru> Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed 18-03-26 12:55:49, Shakeel Butt wrote: [...] > IMO we should actually deprecate compact_unevictable_allowed and always allow > compaction for unevictable memory. We should decouple the notion of mlocked > memory from the pinned/unmovable memory. Pinned memory has much more > consequences on the system related to fragmentation and availability of larger > folios than mlocked memory. If there are applications which need unmovable > memory, they should request it explicitly. I don't think there is an API for > such memory but for such use-cases, it makes sense to have an explicit API. That would be really hard to do in a backward compatible way and there are workloads (e.g. RT) where mlock is supposed to imply even no minor faults. -- Michal Hocko SUSE Labs