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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: E9ED2120008 X-Stat-Signature: 9x19kmks5t3fydzzyawy154dyqawtwe1 X-HE-Tag: 1678414085-406309 X-HE-Meta: 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 ZR+y6v3l x1n0xZsGg1hBDJ2HTJZd8EutoymD5+vBbrFQTb+im7xFaA0A/wQ3Uh6i6XNyVXSRQekQtQrrv1rgri7MgHVVB5+9121wKC3gi78Ku8FrbOcBYtLhy6mFwhGeRcBFyKSo4dhDrzm1lhUSeeaYM1dJI9sq4Nfvzx48dltQ5giaBYdK17QqOwsJSD5FiT+FW5IgxBuF8RfT2PaoIMYNf0mq1gSDf5IMMMD8BBmJQMpg4ek1ImJGD0tY375Sfmz/Dywkbqn0XZoCaQ2DYaF3XLRi+wMy2ONCXpJ8SYOx+XU1Zmrsp7Ml9G8pcg8uDfiVlkgZMQ/MTGfCjDR9fOEPZ5E+eZEfCp+iQWPIJuojMx8WDlyqXAM+6OIfMcg31wYxsQd6Yz9OOx+0iasciR96Dl6ay0960sbew7k2xpKffW/scf+O/HBrPNPAAh14wxg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sat, Feb 18, 2023 at 02:38:40PM -0800, Yosry Ahmed wrote: > ==================== Intro ==================== > Currently, using zswap is dependent on swapfiles in an unnecessary > way. To use zswap, you need a swapfile configured (even if the space > will not be used) and zswap is restricted by its size. There's also overlap with zram too. zswap uses zpool and so does its compression backends (zbud, zsmalloc, z3fold), but zram does not. Vitaly did a great job at presenting some overlap between all this before, so perhaps we can summon him as I'd imagine he'd be interested. https://lpc.events/event/4/contributions/551/attachments/364/597/zram-decouple.pdf FWIW we've been using zswap with the whole intention of *never* touching disk on purpose for years now on kdevops with the goal to just do compression of memory and avoid having to mess with a block device as preamble. This is done on the hypervisor with tons of guests, that together with KSM saves *huge* amount of memory: https://github.com/linux-kdevops/kdevops/blob/master/docs/kernel-ci/kernel-ci-hypervisor-tuning.md Luis