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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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: xt8mstw8hmijpx85jx43eaq6jc9di31r X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: DE8DF1C0003 X-HE-Tag: 1790236422-436536 X-HE-Meta: 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 P3KTHQFc M/baN4Ti7o+PZVw/orMAK248EApcA52dLdXhAxVmZIRaZjMTbdgildZy4cSreyaQymDRVo+66xuz6SzBi4uxi+1gZObZlMVVjvKHh3H7BSaot0VpLyfOOTN6vDNSaG/UCaxbTDU78AxJGegXsc/IlGoDSdn0rHAd+Z/AhJCv/QKV+jnHTkVGXAt1P+wGSMd35yP1ZoLhmT+THJ+rCS7cdlHeDYTNVQoV6cj7PKq4IE0pBryMEbwvxbol1CuDTHSEqZH5nRM5ZlfcKqXObVq4TwcJqz/zBN/PljSZOfLimUox7n/fALfXfmsu80sVorWSONxsCEyDRWwYbnwoKKtWk+ziX/3Qi67OgyWfh0Rjk07CJ1XIN0m//IKS/rTmWTdPP+eDNwwkGGrACFqAsWw0F8ckMz+mJfJjW1SQ7 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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!