On Tue, Mar 4, 2025 at 11:08 AM Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> wrote: > > * Vlastimil Babka <vbabka@xxxxxxx> [250304 05:55]: > > On 2/25/25 21:26, Suren Baghdasaryan wrote: > > > On Mon, Feb 24, 2025 at 1:12 PM Suren Baghdasaryan <surenb@xxxxxxxxxx> wrote: > > >> > > >> > > > >> > > The values represent the total time it took to perform mmap syscalls, less is > > >> > > better. > > >> > > > > >> > > (1) baseline control > > >> > > Little core 7.58327 6.614939 (-12.77%) > > >> > > Medium core 2.125315 1.428702 (-32.78%) > > >> > > Big core 0.514673 0.422948 (-17.82%) > > >> > > > > >> > > (2) baseline control > > >> > > Little core 7.58327 5.141478 (-32.20%) > > >> > > Medium core 2.125315 0.427692 (-79.88%) > > >> > > Big core 0.514673 0.046642 (-90.94%) > > >> > > > > >> > > (3) baseline control > > >> > > Little core 7.58327 4.779624 (-36.97%) > > >> > > Medium core 2.125315 0.450368 (-78.81%) > > >> > > Big core 0.514673 0.037776 (-92.66%) > > > > > > (4) baseline control > > > Little core 7.58327 4.642977 (-38.77%) > > > Medium core 2.125315 0.373692 (-82.42%) > > > Big core 0.514673 0.043613 (-91.53%) > > > > > > I think the difference between (3) and (4) is noise. > > > Thanks, > > > Suren. > > > > Hi, as we discussed yesterday, it would be useful to set the baseline to > > include everything before sheaves as that's already on the way to 6.15, so > > we can see more clearly what sheaves do relative to that. So at this point > > it's the vma lock conversion including TYPESAFE_BY_RCU (that's not undone, > > thus like in scenario (4)), and benchmark the following: > > > > - baseline - vma locking conversion with TYPESAFE_BY_RCU > > - baseline+maple tree node reduction from mm-unstable (Liam might point out > > which patches?) > > Sid's patches [1] are already in mm-unstable. > > > > - the above + this series + sheaves enabled for vm_area_struct cache > > - the above + full maple node sheaves conversion [1] > > - the above + the top-most patches from [1] that are optimizations with a > > tradeoff (not clear win-win) so it would be good to know if they are useful > > > > [1] currently the 4 commits here: > > https://web.git.kernel.org/pub/scm/linux/kernel/git/vbabka/linux.git/log/?h=slub-percpu-sheaves-v2-maple > > from "maple_tree: Sheaf conversion" to "maple_tree: Clean up sheaf" > > but as Liam noted, they won't cherry pick without conflict once maple tree > > node reduction is backported, but he's working on a rebase > > Rebased maple tree sheaves, patches are here [2]. Hi Folks, Sorry for the delay. I got the numbers last week but they looked a bit weird, so I reran the test increasing the number of iterations to make sure noise is not a factor. That took most of this week. Below are the results. Please note that I had to backport the patchsets to 6.12 because that's the closest stable Android kernel I can use. I measure cumulative time to execute mmap syscalls, so the smaller the number the better mmap performance is: baseline: 6.12 + vm_lock conversion and TYPESAFE_BY_RCU config1: baseline + Sid's patches [1] config2: sheaves RFC config3: config1 + vm_area_struct with sheaves config4: config2 + maple_tree Sheaf conversion [2] config5: config3 + 2 last optimization patches from [3] config1 config2 config3 config4 config5 Little core -0.10% -10.10% -12.89% -10.02% -13.64% Mid core -21.05% -37.31% -44.97% -15.81% -22.15% Big core -17.17% -34.41% -45.68% -11.39% -15.29% [1] https://lore.kernel.org/linux-mm/20250227204823.758784-1-sidhartha.kumar@xxxxxxxxxx/ [2] https://www.infradead.org/git/?p=users/jedix/linux-maple.git;a=shortlog;h=refs/heads/sheaves_rebase_20250304 [3] https://web.git.kernel.org/pub/scm/linux/kernel/git/vbabka/linux.git/log/?h=slub-percpu-sheaves-v2-maple
