There is another aspect, though - I had missed it in the thread, but the question Nadia was addressing is: how to tell I am bound? The way we currently do it is to compare our cpuset against the local cpuset - if we are on a subset, then we know we are bound.
So if all hwloc returns to us is our cpuset, then we cannot make that determination. Yet I do see a utility as well in only showing our own cpus. Would it make sense to add a field to the hwloc_obj_t that contains the "accessible" cpus? Or a flag indicating "you are bound to a subset of all available cpus"? Really, all we need is the flag - but we could compute it ourselves if we had the larger scope info. On Feb 9, 2012, at 5:53 AM, Jeff Squyres wrote: > On Feb 9, 2012, at 7:50 AM, Chris Samuel wrote: > >>> Just so that I understand this better -- if a process is bound in a >>> cpuset, will tools like hwloc's lstopo only show the Linux >>> processors *in that cpuset*? I.e., does it not have any >>> visibility of the processors outside of its cpuset? >> >> I believe that was the intention - there's no real benefit to knowing >> about resources that you can't access or use (and will likely get an >> error if you do) to my mind. > > The real question, however, is how are IO devices represented if you don't do > WHOLE_SUBSYSTEM? I.e., what about IO devices that are not local to the > socket of your cpuset, for example? > > Take this sample image, for example: > > http://www.open-mpi.org/projects/hwloc/devel09-pci.png > > What if my cpuset is only on Socket P#0? What exactly will be reported via > (WHOLE_SUBSYSTEM | HWLOC_TOPOLOGY_FLAG_WHOLE_IO)? > > IO devices is something that we do have an interest in reporting so that we > can tell the "distance" to them, for example. > > -- > Jeff Squyres > jsquy...@cisco.com > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > > _______________________________________________ > devel mailing list > de...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/devel
