From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (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 DCE784CDDE6; Mon, 21 Sep 2026 16:46:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=96.67.55.147 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790009183; cv=none; b=fntMOyv+Ee104R88lBGTZ8rzC+60BFHvzVnSW6b5Ljp3M0xCYBak4qpoRP9xitoFR6aGzISG4qSEcIofY4uZ2Nn+IPZ3HZBwi2f/KafOFGXaz83ocaczbIJJojJFV8B/yv0TqHNdTxqlpa31zrKQqW2wEXta61fIbvvx+Yj8UrQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790009183; c=relaxed/simple; bh=kL4CEDMA8FMuYyjEV8N5GomlHACJM5bczC87qdc9IMA=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=PgNDLUs6+OCf78TJSRc7FOm1hVofwLSCYYMZDYwCsFWpr/4uRnXvA5vmq0JB0ykJHTBwL9d3alDD/ISP+P5MQQ26wF+aI476FdW/bNlBdH4P8VsPyPGoPXF+Ua0D5tp12W4+HX1Zg6vf7W+vRETiYtvzRWvDrJQYU/XbbRIPKPI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=surriel.com; spf=pass smtp.mailfrom=surriel.com; dkim=pass (2048-bit key) header.d=surriel.com header.i=@surriel.com header.b=g8vB+Dr1; arc=none smtp.client-ip=96.67.55.147 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=surriel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=surriel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=surriel.com header.i=@surriel.com header.b="g8vB+Dr1" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=surriel.com ; s=mail; h=MIME-Version:Content-Transfer-Encoding:Content-Type:References: In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID; bh=zrXZhXeHCiziPKli3BDOjO0c3/5kNvHCXof2G6qqIq4=; b=g8vB+D r1ZVtzugVo77DTqAvz/KTqoxoDNgaB2lGTinyee0pOW78RM0msN+6Ov7Ism32bQAJhW59xy2e0di1 Gf5fdaShuS2/oTWKyr/3S4sPYfFE5RDTEkjh8pxk50BpxC0IOAPVg6u2i6H4mSNOGzevTVBrRU6Gb nKuoQ2F/l7OuOAIhvAtgUnbtZDKcveAJZH49c81i7iuBSvjem8a3ddr/BwoWqMsnslOdlOwcRCDGI GtpEEvr45PFJ01JV8O+S54y01gbUYXneUrrndblzqElhfiR5qeJSyqSJN3pDmHvGN/QJx/3t5gZJT KeZnB6BktLeoJtqRT7bAEGOYQFUw==; Received: from [2601:18c:8100:a0e0:5a47:caff:fe78:8708] by shelob.surriel.com with esmtpsa (TLS1.3) tls TLS_AES_256_GCM_SHA384 (Exim 4.99.5) (envelope-from ) id 1x8gzz-0000000D4jK-3vpf; Mon, 21 Sep 2026 16:36:12 +0000 Message-ID: <785353ef79844e81a8cd97e87b00ef1f785b15e5.camel@surriel.com> Subject: Re: Path forward for Virtualized Swap? From: Rik van Riel To: Chris Li Cc: Gregory Price , Johannes Weiner , Baoquan He , Nhat Pham , Kairui Song , Michal Hocko , Roman Gushchin , Shakeel Butt , Yosry Ahmed , David Hildenbrand , Muchun Song , Kemeng Shi , Barry Song , YoungJun Park , Chengming Zhou , "Lorenzo Stoakes (Oracle)" , "Liam R. Howlett" , "Vlastimil Babka (SUSE)" , Mike Rapoport , Suren =?UTF-8?Q?Baghdasaryan=EF=BF=BC?= , Qi Zheng , Axel Rasmussen , Yuanchu Xie , Wei Xu , Wenchao Hao , Jonathan Corbet , Hugh Dickins , Baolin Wang , Tejun Heo , Michal =?ISO-8859-1?Q?Koutn=FD?= , Shuah Khan , Kunwu Chan , Meta kernel team , Linux Memory Management List , Linux Kernel Mailing List , linux-doc@vger.kernel.org, "open list:CONTROL GROUP - MEMORY RESOURCE CONTROLLER (MEMCG)" , Andrew Morton , Kairui Song , Joshua Hahn Date: Mon, 21 Sep 2026 12:36:08 -0400 In-Reply-To: References: Autocrypt: addr=riel@surriel.com; prefer-encrypt=mutual; keydata=mQENBFIt3aUBCADCK0LicyCYyMa0E1lodCDUBf6G+6C5UXKG1jEYwQu49cc/gUBTTk33A eo2hjn4JinVaPF3zfZprnKMEGGv4dHvEOCPWiNhlz5RtqH3SKJllq2dpeMS9RqbMvDA36rlJIIo47 Z/nl6IA8MDhSqyqdnTY8z7LnQHqq16jAqwo7Ll9qALXz4yG1ZdSCmo80VPetBZZPw7WMjo+1hByv/ lvdFnLfiQ52tayuuC1r9x2qZ/SYWd2M4p/f5CLmvG9UcnkbYFsKWz8bwOBWKg1PQcaYHLx06sHGdY dIDaeVvkIfMFwAprSo5EFU+aes2VB2ZjugOTbkkW2aPSWTRsBhPHhV6dABEBAAG0HlJpayB2YW4gU mllbCA8cmllbEByZWRoYXQuY29tPokBHwQwAQIACQUCW5LcVgIdIAAKCRDOed6ShMTeg05SB/986o gEgdq4byrtaBQKFg5LWfd8e+h+QzLOg/T8mSS3dJzFXe5JBOfvYg7Bj47xXi9I5sM+I9Lu9+1XVb/ r2rGJrU1DwA09TnmyFtK76bgMF0sBEh1ECILYNQTEIemzNFwOWLZZlEhZFRJsZyX+mtEp/WQIygHV WjwuP69VJw+fPQvLOGn4j8W9QXuvhha7u1QJ7mYx4dLGHrZlHdwDsqpvWsW+3rsIqs1BBe5/Itz9o 6y9gLNtQzwmSDioV8KhF85VmYInslhv5tUtMEppfdTLyX4SUKh8ftNIVmH9mXyRCZclSoa6IMd635 Jq1Pj2/Lp64tOzSvN5Y9zaiCc5FucXtB9SaWsgdmFuIFJpZWwgPHJpZWxAc3VycmllbC5jb20+iQE +BBMBAgAoBQJSLd2lAhsjBQkSzAMABgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIXgAAKCRDOed6ShMTe g4PpB/0ZivKYFt0LaB22ssWUrBoeNWCP1NY/lkq2QbPhR3agLB7ZXI97PF2z/5QD9Fuy/FD/jddPx KRTvFCtHcEzTOcFjBmf52uqgt3U40H9GM++0IM0yHusd9EzlaWsbp09vsAV2DwdqS69x9RPbvE/Ne fO5subhocH76okcF/aQiQ+oj2j6LJZGBJBVigOHg+4zyzdDgKM+jp0bvDI51KQ4XfxV593OhvkS3z 3FPx0CE7l62WhWrieHyBblqvkTYgJ6dq4bsYpqxxGJOkQ47WpEUx6onH+rImWmPJbSYGhwBzTo0Mm G1Nb1qGPG+mTrSmJjDRxrwf1zjmYqQreWVSFEt26tBpSaWsgdmFuIFJpZWwgPHJpZWxAZmIuY29tP okBPgQTAQIAKAUCW5LbiAIbIwUJEswDAAYLCQgHAwIGFQgCCQoLBBYCAwECHgECF4AACgkQznneko TE3oOUEQgAsrGxjTC1bGtZyuvyQPcXclap11Ogib6rQywGYu6/Mnkbd6hbyY3wpdyQii/cas2S44N cQj8HkGv91JLVE24/Wt0gITPCH3rLVJJDGQxprHTVDs1t1RAbsbp0XTksZPCNWDGYIBo2aHDwErhI omYQ0Xluo1WBtH/UmHgirHvclsou1Ks9jyTxiPyUKRfae7GNOFiX99+ZlB27P3t8CjtSO831Ij0Ip QrfooZ21YVlUKw0Wy6Ll8EyefyrEYSh8KTm8dQj4O7xxvdg865TLeLpho5PwDRF+/mR3qi8CdGbkE c4pYZQO8UDXUN4S+pe0aTeTqlYw8rRHWF9TnvtpcNzZw== Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.60.2 (3.60.2-1.fc44) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Mon, 2026-09-21 at 06:31 -1000, Chris Li wrote: >=20 > Give me some real-world examples of people hitting this kind of > limit. > e.g. MAX(%)=C2=A0 > 100% and still have a usesable system. I suspect that > with 100% zswap usage, the system becomes unusable. Please show me a > real world case that proves me wrong. >=20 Here's my desktop system right now. The amount of Zswapped is more than twice AnonPages, and the system stays perfectly usable. $ grep -E '(Anon|Zswap|GPU|Swap)' /proc/meminfo=20 SwapCached: 252340 kB SwapTotal: 41523604 kB SwapFree: 9802088 kB Zswap: 8812236 kB Zswapped: 24927876 kB AnonPages: 11615760 kB AnonHugePages: 1402880 kB GPUActive: 13112428 kB GPUReclaim: 95980 kB This is also an example where I cannot really predict how much zswap space I need, because that depends on what AI model is loaded, which drives the GPUActive number, as well as the number of browser tabs. The system is perfectly responsive. --=20 All Rights Reversed.