On Fri, May 21, 2021 at 03:57:20PM -0700, Dave Hansen wrote: > On 5/21/21 3:28 AM, Mel Gorman wrote: > > This introduces a new sysctl vm.percpu_pagelist_high_fraction. It is > > similar to the old vm.percpu_pagelist_fraction except it only adjusts > > pcp->high to potentially reduce zone->lock contention while preserving > > allocation latency when PCP lists have to be refilled. > > Look at me... Five patches later and I already forgot what the old one > did and why it stinks. I wonder if you might do a wee bit of compare > and contrast. Something like: > > The old vm.percpu_pagelist_fraction increased both the batch and > high limits for the per-cpu page allocator. Its worst feature > was that it led to absurdly large batch sizes that incurred > nasty worst-case allocation latency. > > This new sysctl in comparison... > > Anyway, the approach looks sound to me. The batch size isn't important > now, especially given the auto-scaling in patch 4. > > Acked-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Thanks, I updated the changelog and hopefully it is better. -- Mel Gorman SUSE Labs
