On Sun, Feb 26, 2023 at 10:35 PM Yin, Fengwei <fengwei.yin@xxxxxxxxx> wrote: > > Hi Andrew, Shakeel, > > On Tue, 2023-01-31 at 10:26 -0800, Shakeel Butt wrote: > > +per-cpu memory maintainers for FYI. > > > > Thread started at > > https://lore.kernel.org/linux-mm/202301301057.e55dad5b-oliver.sang@xxxxxxxxx/ > > > > On Mon, Jan 30, 2023 at 9:57 PM Shakeel Butt <shakeelb@xxxxxxxxxx> > > wrote: > > > > > [...] > > > > > > > > We could cut down the number of calls to pcpu_alloc() by a factor > > > > of 4 > > > > by having a pcpu_alloc_bulk() that would allocate all four RSS > > > > counters > > > > at once. > > > > > > > > Just throwing out ideas ... > > > > > > Thanks, I will take a stab at pcpu_alloc_bulk() and will share the > > > result tomorrow. > > > > > > > OK, not a one day effort. > > > > Andrew, which option do you prefer? > > > > 1. Keep the patches as the test workload (fork ping pong) is not a > > representative of real world workload and work on improving > > pcpu_alloc() for 6.4+. > > > > 2. Revert the patches for now, improve pcpu_alloc() and re-introduce > > the patches once we confirm that fork-ping-pong is not regressed > > anymore. > This performance regression still can be reproduced on latest master > branch. So we took option1 here. Right? Thanks. > Yes unless some real workload reports regression. Shakeel
