[PATCH] sched/numa: Stagger NUMA balancing scan periods for new threads v2

Changelog since v1 o Cosmetic changes and documentation (ingo) o Note results were very similar to v1 and so I didn't update the changelog Threads share an address space and each can change the protections of the same address space to trap NUMA faults. This is redundant and potentially counter-pro

Re: [PATCH] sched/numa: Stagger NUMA balancing scan periods for new threads

On Fri, Apr 27, 2018 at 08:50:57AM +0200, Ingo Molnar wrote: > > 4.17.0-rc1 4.17.0-rc1 > >vanilla stagger-v1r1 > > sys-time-bt.D 48.78 ( 0.00%) 48.22 ( 1.15%) > > sys-time-cg.D 25.31 ( 0.00

Re: [PATCH] sched/numa: Stagger NUMA balancing scan periods for new threads

* Mel Gorman wrote: > The different in headline performance across a range of machines and > workloads is marginal but the system CPU usage is reduced due to less scan > activity. The following is the time reported by NAS Parallel Benchmark > using unbound openmp threads and a D size class. >

[PATCH] sched/numa: Stagger NUMA balancing scan periods for new threads

Threads share an address space and each can change the protections of the same address space to trap NUMA faults. This is redundant and potentially counter-productive as any thread doing the update will suffice. Potentially only one thread is required but that thread may be idle or it may not have