Re: [hwloc-users] Process and thread binding

2011-09-12 Thread Samuel Thibault
Gabriele Fatigati, le Mon 12 Sep 2011 15:50:45 +0200, a écrit : > thanks very much for your explanations. But I don't understand why a process > inherits core bound of his threads On Linux, there is no such thing as "process binding", only "thread binding". hwloc emulates the former by using the

Re: [hwloc-users] Process and thread binding

2011-09-12 Thread Gabriele Fatigati
Ok Brice, thanks very much for your explanations. But I don't understand why a process inherits core bound of his threads according to your example: >It worked because you never mixed it with single thread binding. If you bind process X to >coreA and then thread Y of process X to coreB, what you

Re: [hwloc-users] Process and thread binding

2011-09-12 Thread Brice Goglin
Le 12/09/2011 14:17, Gabriele Fatigati a écrit : > Mm, and why? In a hybrid code ( MPI + OpenMP), my idea is to bind a > single MPI process in one core, and his threads in other cores. > Otherwise I have all threads that runs on a single core. > The usual way to do that is to first bind the

Re: [hwloc-users] Process and thread binding

2011-09-12 Thread Gabriele Fatigati
Ok, >A process is a container that contains one or several threads. The binding is where >something can run. It's normal that "where a process can run" is "where any of its >threads can run", which means it's the logical OR of their binding. Ok, now it's clear. I'm using

Re: [hwloc-users] Process and thread binding

2011-09-12 Thread Brice Goglin
Le 12/09/2011 13:58, Gabriele Fatigati a écrit : > Hi Brice, > > but in the manual is not written that get_cpubind() returns the > logical OR of the binding of all threads... I ever understand that > returns the bind of the calloer, where the caller can be process or > thread.. A process is a

Re: [hwloc-users] Process and thread binding

2011-09-12 Thread Gabriele Fatigati
Hi Brice, but in the manual is not written that get_cpubind() returns the logical OR of the binding of all threads... I ever understand that returns the bind of the calloer, where the caller can be process or thread.. I'm mixing bind of process and threads, and I've noted that if the process and

Re: [hwloc-users] Process and thread binding

2011-09-12 Thread Brice Goglin
Le 12/09/2011 13:29, Gabriele Fatigati a écrit : > Hi Birce, > > I'm so confused.. > > I'm binding MPI processes with set_cpu_bind and it works well. The > problem is when I try to bind process and threads. > > It seem that thread process influence bind of main thread. > > And from hwloc manual:

Re: [hwloc-users] Process and thread binding

2011-09-12 Thread Brice Goglin
Le 12/09/2011 12:52, Gabriele Fatigati a écrit : > Dear hwloc users, > > I'm binding process in a NUMA node and also associated OpenMP threads. > I've noted that, if I bind execution of all on different cores in > the same NUMA node , it works well. > > If I bind process in NUMA node 0 for