From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta0.migadu.com (out-99.mta0.migadu.com [91.218.175.99]) (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 331474307B0 for ; Thu, 24 Sep 2026 07:53:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.99 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790236426; cv=none; b=h4it9CzdhzyoarILMT9QG6eg49A/08Gr3rZTeLUnQYZvxVDR8qBOapIlV1HwWLFUxOtcx3YEVSrJqVUxZCfqIaKtVuX2CBq1ADVx1DcFS9gmbLeL/nTtNcXl0KAqNYA6M5LLTKpp6HB2XFDQsGkNBaZTkQg6pFK6y6NGbOjsVtk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790236426; c=relaxed/simple; bh=tmFKVXcIZq7e/z6sePm5F4/lrwU40o91QzXOAC74BWg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=AVacVI44wVklAqmXeqiufLRtIecfXwbicPCCYP8iiQRzGzPjDsuOumsMBjijDdxQn0t2IPg/DMLzCKaTVM6uQ4SQooLjypMCxj26nnVm2rIIK3EtpKaDQO/j/HgIG7hGn+hhxvMGYK/TcO1dtuiP6LHm9d0ebcySDp2d+Vn5u2o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=MuDzBozR; arc=none smtp.client-ip=91.218.175.99 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="MuDzBozR" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=tmFKVXcIZq7e/z6sePm5F4/lrwU40o91QzXOAC74BWg=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1790236422; v=1; x=1790841222; b=MuDzBozRitngDeYt7LdGDXXgd0dNYPast5NxG3UNIJbOj6z4nn7SDbGpvBsoyk009+YFxZ4U J99oOpwwlSnJchoEo2mmdMpJFARKLqMF/TpA7DI1wzNDVq0iNV97Gul4Hk4UpwVcSsuQuKh34gr j481XSTM6CZnZM1FCQxXFv9I= X-Envelope-To: linux-kernel@vger.kernel.org Received: by mta11.migadu.com with ESMTPS id 8c9537f07561259a; Thu, 24 Sep 2026 07:53:41 +0000 X-Mizu-Trace-ID: 8c9537f07561259a X-Migadu-Flow: FLOW_OUT Date: Thu, 24 Sep 2026 15:53:33 +0800 From: Baoquan He To: Klara Modin Cc: Chris Li , Rik van Riel , Gregory Price , Johannes Weiner , 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?B?QmFnaGRhc2FyeWFu77+8?= , 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 Subject: Re: Path forward for Virtualized Swap? Message-ID: References: <83539be885f15bb567b30264f5f62e718f4a9fd0.camel@surriel.com> <5a7ad159b2fabf377b7e1fc4248c433287ac11fb.camel@surriel.com> 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-Disposition: inline In-Reply-To: On 09/24/26 at 09:20am, Klara Modin wrote: > On 2026-09-24 13:51:50 +0800, Baoquan He wrote: > > On 09/23/26 at 02:52pm, Klara Modin wrote: > > > Hi, > > > > ... > > > > > > Chiming in as more of a user perspective. > > > > > > On my 4 GiB BPI-F3, I can reach more than 10:1 compression ratio on > > > zswap during some parts when building GCC 17 snapshots. E.g: > > > > > > MemTotal: 3966864 kB > > > SwapCached: 31872 kB > > > SwapTotal: 16777212 kB > > > SwapFree: 16638128 kB > > > Zswap: 280140 kB > > > Zswapped: 2859840 kB > > > AnonPages: 2927376 kB > > > AnonHugePages: 1409024 kB > > > > > > While this is 72 % rather than the 100 % you asked for, I think this > > > shows that what size a potential limit on the uncompressed size of zswap > > > is suitable heavily depends on the workload. > > > > > > I have been using vswap consistently on all my machines since about > > > August, and I have also tried one or two versions of xswap (but the > > > current lack of writeback makes it inconvenient for me). I really > > > > Thanks for testing xswap and reporting issue on xswap rfc v3. > > > > xswap has writeback now. I only built foundation for xswap, while > > writeback part was left to other people for collaboration. Finally > > I added it. > > > > [RFC PATCH 00/17] mm, swap: xswap writeback to a physical backend > > https://lore.kernel.org/all/20260920072043.430390-1-hebaoquan@kylinos.cn/T/#u > > > > Thanks, I'll give it another try when I have time. Sure, no hurry. Thanks a lot!