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charset="UTF-8" X-Stat-Signature: zihp1idbxjn3hsc454nd3z9zj9j1jipw X-Rspamd-Server: rspam09 X-Rspam-User: X-Rspamd-Queue-Id: CF3D2C000D X-HE-Tag: 1772642763-260756 X-HE-Meta: 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 vkOMDoe5 Dvssn5TB3jqG0bUa5FG7GrAHm/AK2udQi194s5tlqG/7KOgmoejuBN5PazgdqEk5DeI4tlNVufAFQ0cwU9ZHLAI26mk5iwatk41UE7tpX6BsCsrN1LI38XRXRcP6HxTJw0ruqufqFCMDi+uaBban5voQM3VKLIgcAoh5Ik9rQ9bLzPPSoqRTeb/vYlDpqPawu9ieYNpCVfzlGBNakmI9KqTyJWtljm/3RpOYD4wGmEc2gaojcdcs+NI5SdQVJ5uGdhpiuD6MkeRyWOL9nNjKiLKIV+IM/GmiqSubYKlZgWlydqeFF5/95sGNhGITkqo9L0NXKda5i/EQW6mz2OZ8s0LAhL8b11YyrMl+Z Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > > AFAICT the only zswap-specific part is the actual stat indexes, what > > if these are parameterized at the zsmalloc pool level? AFAICT zswap > > and zram will never share a pool. > > TBH, if we were to start from scratch, these should be zsmalloc > counters not zswap counters. Only zsmalloc knows about the memory > placement and real memory consumption (i.e taking into account > intra-slot wasted space) - this information is abstracted away from > all of the callers. I agree, but we cannot change the zswap stats now that we added them. Keep in mind that when they were added zsmalloc was not the only backend. > And if/when zram supports cgroup tracking, memory > used by zswap and memory used by zram is indistinguishable, no? It is distinguishable as long as they use different zsmalloc pools, I don't see why we'd need to share a pool. > Anyway, Joshua, do you think this is doable? Seems promising to me, > but idk if it will be clean to implement or not. Not sure what you mean here? Changing the stats to be zsmalloc-based? IIUC we can't do this without breaking userspace.