Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-26 Thread Christopher Lameter
On Fri, 22 Dec 2017, kemi wrote: > > I think you are fighting a lost battle there. As evident from the timing > > constraints on packet processing in a 10/40G you will have a hard time to > > process data if the packets are of regular ethernet size. And we alrady > > have 100G NICs in operation

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-22 Thread Michal Hocko
On Thu 21-12-17 18:31:19, kemi wrote: > > > On 2017年12月21日 16:59, Michal Hocko wrote: > > On Thu 21-12-17 16:23:23, kemi wrote: > >> > >> > >> On 2017年12月21日 16:17, Michal Hocko wrote: > > [...] > >>> Can you see any difference with a more generic workload? > >>> > >> > >> I didn't see obvious

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-21 Thread kemi
On 2017年12月22日 01:10, Christopher Lameter wrote: > On Thu, 21 Dec 2017, kemi wrote: > >> Some thinking about that: >> a) the overhead due to cache bouncing caused by NUMA counter update in fast >> path >> severely increase with more and more CPUs cores >> b) AFAIK, the typical usage scenario

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-21 Thread Christopher Lameter
On Thu, 21 Dec 2017, kemi wrote: > Some thinking about that: > a) the overhead due to cache bouncing caused by NUMA counter update in fast > path > severely increase with more and more CPUs cores > b) AFAIK, the typical usage scenario (similar at least)for which this > optimization can >

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-21 Thread kemi
On 2017年12月21日 16:59, Michal Hocko wrote: > On Thu 21-12-17 16:23:23, kemi wrote: >> >> >> On 2017年12月21日 16:17, Michal Hocko wrote: > [...] >>> Can you see any difference with a more generic workload? >>> >> >> I didn't see obvious improvement for will-it-scale.page_fault1 >> Two reasons for

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-21 Thread Michal Hocko
On Thu 21-12-17 16:23:23, kemi wrote: > > > On 2017年12月21日 16:17, Michal Hocko wrote: [...] > > Can you see any difference with a more generic workload? > > > > I didn't see obvious improvement for will-it-scale.page_fault1 > Two reasons for that: > 1) too long code path > 2) server zone lock

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-21 Thread kemi
On 2017年12月21日 16:17, Michal Hocko wrote: > On Thu 21-12-17 16:06:50, kemi wrote: >> >> >> On 2017年12月20日 18:12, Michal Hocko wrote: >>> On Wed 20-12-17 13:52:14, kemi wrote: On 2017年12月19日 20:40, Michal Hocko wrote: > On Tue 19-12-17 14:39:24, Kemi Wang wrote: >> We have

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-21 Thread Michal Hocko
On Thu 21-12-17 16:06:50, kemi wrote: > > > On 2017年12月20日 18:12, Michal Hocko wrote: > > On Wed 20-12-17 13:52:14, kemi wrote: > >> > >> > >> On 2017年12月19日 20:40, Michal Hocko wrote: > >>> On Tue 19-12-17 14:39:24, Kemi Wang wrote: > We have seen significant overhead in cache bouncing

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-21 Thread kemi
On 2017年12月20日 18:12, Michal Hocko wrote: > On Wed 20-12-17 13:52:14, kemi wrote: >> >> >> On 2017年12月19日 20:40, Michal Hocko wrote: >>> On Tue 19-12-17 14:39:24, Kemi Wang wrote: We have seen significant overhead in cache bouncing caused by NUMA counters update in multi-threaded page

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-20 Thread kemi
On 2017年12月20日 18:12, Michal Hocko wrote: > On Wed 20-12-17 13:52:14, kemi wrote: >> >> >> On 2017年12月19日 20:40, Michal Hocko wrote: >>> On Tue 19-12-17 14:39:24, Kemi Wang wrote: We have seen significant overhead in cache bouncing caused by NUMA counters update in multi-threaded page

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-20 Thread Michal Hocko
On Wed 20-12-17 13:52:14, kemi wrote: > > > On 2017年12月19日 20:40, Michal Hocko wrote: > > On Tue 19-12-17 14:39:24, Kemi Wang wrote: > >> We have seen significant overhead in cache bouncing caused by NUMA counters > >> update in multi-threaded page allocation. See 'commit 1d90ca897cb0 ("mm: > >>

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-19 Thread kemi
On 2017年12月19日 20:40, Michal Hocko wrote: > On Tue 19-12-17 14:39:24, Kemi Wang wrote: >> We have seen significant overhead in cache bouncing caused by NUMA counters >> update in multi-threaded page allocation. See 'commit 1d90ca897cb0 ("mm: >> update NUMA counter threshold size")' for more

Re: [PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-19 Thread Michal Hocko
On Tue 19-12-17 14:39:24, Kemi Wang wrote: > We have seen significant overhead in cache bouncing caused by NUMA counters > update in multi-threaded page allocation. See 'commit 1d90ca897cb0 ("mm: > update NUMA counter threshold size")' for more details. > > This patch updates NUMA counters to a

[PATCH v2 3/5] mm: enlarge NUMA counters threshold size

2017-12-18 Thread Kemi Wang
We have seen significant overhead in cache bouncing caused by NUMA counters update in multi-threaded page allocation. See 'commit 1d90ca897cb0 ("mm: update NUMA counter threshold size")' for more details. This patch updates NUMA counters to a fixed size of (MAX_S16 - 2) and deals with global