On Sun, 2018-06-03 at 00:51 +0000, Song Liu wrote: > > Just to check: in the workload where you're seeing this problem, > > are > > you using an mm with many threads? I would imagine that, if you > > only > > have one or two threads, the bit operations aren't so bad. > > Yes, we are running netperf/netserver with 300 threads. We don't see > this much overhead in with real workload.
We may not, but there are some crazy workloads out there in the world. Think of some Java programs with thousands of threads, causing a million context switches a second on a large system. I like Andy's idea of having one cache line with a cpumask per node. That seems like it will have fewer downsides for tasks with fewer threads running on giant systems. I'll throw out the code I was working on, and look into implementing that :) -- All Rights Reversed.
signature.asc
Description: This is a digitally signed message part
