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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: BF15140013 X-Stat-Signature: pcu6ahnagfbo7obg9aoqpt85ufht749m X-Rspam-User: X-HE-Tag: 1722357053-16954 X-HE-Meta: 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 n1eQS8AM f0TqE/Q7HC78W6noKdmIDdHBAIeiXR3x9IUAA+pGSOuBXAVLdJRkhuxuKE27MogAvDhLj5HXKHBNOQONHVwDH3I4IqL6JvylYvP1ZHw2lzdAPRgSZh6kbrveE3qAgjs7OwVQ+3J3PIQpVqyLenafXVfBkV7zxuv8WqgDhToqhYS2veCIDp88FFMK5CMlK0TOOiaHn7/vJWU+py8YIIQml+hmZ4igkBsXbKdieP5wtR6W7y6EIphm5XBxpHK4Fy6QoyJzwizoI3P/sXa8+sqk8f0neo039oPv6zA/+ky9+oBjX3NykcoBWb7mQ+z7cWuDb9Nq72iHeDvPfKOrPN3tjmRCmPwF2Nw5PfAdC8UTql9K0QGqG6seY1v0eZKOnURXkcM0+oJY7MGQRvupffYs+cAaz54o3Hi2KP8rj3jcflG7h4OoQw1I4axLoPIMtvczqCm+9jKigagWJYkM= 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: List-Subscribe: List-Unsubscribe: On Tue, Jul 30, 2024 at 08:11:16AM +1200, Barry Song wrote: > > We also really need to stop optimizing for this weird zram case and move > > people to zswap instead after fixing the various issues. A special > > block device that isn't really a block device and needs various special > > hooks isn't the right abstraction for different zwap strategies. > > My understanding is zRAM is much more popularly used in embedded > systems than zswap. I seldomly(or never) hear who is using zswap > in Android. it seems pointless to force people to move to zswap, in > embedded systems we don't have a backend real block disk device > after zswap. Well, that is the point. zram is a horrible hack that abuses a block device to implement a feature missing the VM layer. Right now people have a reason for it because zswap requires a "real" backing device and that's fine for them and for now. But instead of building VM infrastructure around these kinds of hacks we need to fix the VM infrastructure. Chris Li has been talking about and working towards a proper swap abstraction and that needs to happen.