On Tue, Mar 15, 2022 at 1:44 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > On Tue, Mar 15, 2022 at 01:34:21PM -0400, Brian Geffon wrote: > > On Tue, Mar 15, 2022 at 1:28 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > > > > > On Tue, Mar 15, 2022 at 10:22:21AM -0700, Brian Geffon wrote: > > > > Today it's only possible to write back as a page, idle, or huge. > > > > A user might want to writeback pages which are huge and idle first > > > > as these idle pages do not require decompression and make a good > > > > first pass for writeback. > > > > > > We're moving towards having many different sizes of page in play, > > > not just PMD and PTE sizes. Is this patch actually a good idea in > > > a case where we have, eg, a 32kB anonymous page on a system with 4kB > > > pages? How should zram handle this case? What's our cut-off for > > > declaring a page to be "huge"? > > > > > > > Huge isn't a great term IMO, but it is what it is. ZRAM_HUGE is used > > to identify pages which are incompressible. Since zram is a block > > device which presents PAGE_SIZED blocks, do these new changes which > > involve many different page sizes matter as that seems orthogonal to > > the block subsystem. Correct me if I'm misunderstanding. > > Oh, so ZRAM's concept of huge is not the same as the "huge" in > "hugetlbfs" or "THP"? That's not at all confusing ... I do not disagree, but there isn't much that can be done about it at this point given the sysfs file takes an argument called "huge"
