Le 09/02/2012 14:00, Ralph Castain a écrit : > 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.
Each hwloc object has several "cpuset" fields describing whether CPUs are online or not, and accessible or not. Here are their meaning when the WHOLE_SYSTEM flag is NOT set: * "cpuset" only contains CPUs that are online and accessible * "online_cpuset" is "cpuset" + CPUs that are online but not accessible * "allowed_cpuset" is "cpuset" + CPUs that are accessible but not online * "complete_cpuset" is everything So you can find out that you are "bound" by a Linux cgroup (I am not saying Linux "cpuset" to avoid confusion) by comparing root->cpuset and root->online_cpuset. Brice > 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.
