Re: [hwloc-users] memory binding on Knights Landing

2016-10-16 Thread Christopher Samuel
On 12/10/16 02:03, Dave Love wrote: > For what it's worth, I was misled when I investigated originally by > counting calls of open and not openat, which is what hwloc uses. strace -c can be very handy to give you a quick insight into which system calls are taking the most time (either in a

Re: [hwloc-users] memory binding on Knights Landing

2016-10-11 Thread Dave Love
Brice Goglin writes: > I ran more benchmarks. What's really slow is the reading of all sysfs > files. About 90% of the topology building time is spent there on KNL. > We're reading more than 7000 files (most of them are 6 files for each > hardware thread and 6 files for

Re: [hwloc-users] memory binding on Knights Landing

2016-10-04 Thread Brice Goglin
Le 12/09/2016 04:20, Brice Goglin a écrit : > So what's really slow is reading sysfs and/or inserting all hwloc > objects in the tree. I need to do some profiling. And I am moving the > item "parallelize the discovery" higher in the TODO list :) Brice Hello I ran more benchmarks. What's

Re: [hwloc-users] memory binding on Knights Landing

2016-09-12 Thread Dave Love
Brice Goglin writes: > So what's really slow is reading sysfs and/or inserting all hwloc > objects in the tree. I need to do some profiling. And I am moving the > item "parallelize the discovery" higher in the TODO list :) It didn't seem to scale between systems with the

Re: [hwloc-users] memory binding on Knights Landing

2016-09-12 Thread Dave Love
Brice Goglin writes: > I am not sure where that hwloc for RHEL on KNL is available from. It > might be in Intel's "XPPSL" software suite. I didn't know about that, but it only has hwloc 1.11.2, as in RHEL7 beta, in case the more recent changes for KNL are relevant.

Re: [hwloc-users] memory binding on Knights Landing

2016-09-12 Thread Brice Goglin
Le 08/09/2016 19:17, Brice Goglin a écrit : > >> By the way, is it expected that binding will be slow on it? hwloc-bind >> is ~10 times slower (~1s) than on two-socket sandybridge, and ~3 times >> slower than on a 128-core, 16-socket system. > Binding itself shouldn't be slower. But hwloc's

Re: [hwloc-users] memory binding on Knights Landing

2016-09-09 Thread Brice Goglin
Le 09/09/2016 12:49, Dave Love a écrit : > >> Intel people are carrefully >> working with RedHat so that hwloc is properly packaged for RHEL. I can >> report bugs if needed. > I can't see a recent hwloc for RHEL (e.g. in RHEL7 beta), but don't get > me started on RHEL and HPC... > I am not sure

Re: [hwloc-users] memory binding on Knights Landing

2016-09-09 Thread Dave Love
Brice Goglin writes: > Is there anything to fix on the RPM side? Nothing significant, I think. The update Fedora version needed slight adjustment for hwloc-dump-hwdata, at least. > Intel people are carrefully > working with RedHat so that hwloc is properly packaged for

Re: [hwloc-users] memory binding on Knights Landing

2016-09-09 Thread Dave Love
Jeff Hammond writes: >> By the way, is it expected that binding will be slow on it? hwloc-bind >> is ~10 times slower (~1s) than on two-socket sandybridge, and ~3 times >> slower than on a 128-core, 16-socket system. >> >> Is this a bottleneck in any application? Are

Re: [hwloc-users] memory binding on Knights Landing

2016-09-08 Thread Jeff Hammond
On Thu, Sep 8, 2016 at 8:59 AM, Dave Love wrote: > Brice Goglin writes: > > > Hello > > It's not a feature. This should work fine. > > Random guess: do you have NUMA headers on your build machine ? (package > > libnuma-dev or numactl-devel) > >

Re: [hwloc-users] memory binding on Knights Landing

2016-09-08 Thread Brice Goglin
Hello It's not a feature. This should work fine. Random guess: do you have NUMA headers on your build machine ? (package libnuma-dev or numactl-devel) (hwloc-info --support also report whether membinding is supported or not) Brice Le 08/09/2016 16:34, Dave Love a écrit : > I'm somewhat confused