Le 15/12/2015 07:21, Brice Goglin a écrit : > > > Le 15/12/2015 05:57, Rezaul Karim Raju a écrit : >> *OUTPUT: * >> *Policy-->* buffer(Array: A) *membind [default OS binding] Policy >> is:= 1 [1 refers to *HWLOC_MEMBIND_FIRSTTOUCH >> <https://www.open-mpi.org/projects/hwloc/doc/v1.11.1/a00083.php#ggac9764f79505775d06407b40f5e4661e8a979c7aa78dd32780858f30f47a72cca0>*]* >> *Nodeset --> *buffer(Array: A) bound to nodeset*0x000000ff *with >> contains*:* >> * *node #0 (OS index 0) with 8387047424 bytes of memory >> node #1 (OS index 1) with 8471617536 bytes of memory >> node #2 (OS index 2) with 8471621632 bytes of memory >> node #3 (OS index 3) with 8471617536 bytes of memory >> node #4 (OS index 4) with 8471621632 bytes of memory >> node #5 (OS index 5) with 8471617536 bytes of memory >> node #6 (OS index 6) with 8471621632 bytes of memory >> node #7 (OS index 7) with 8471564288 bytes of memory >> * >> * >> *why it shows allocated memory is bound to all available nodeset..? >> should it not be allocated to a specific nodeset one ..?* >> * >> * > > Hello > > You are confusing the "binding" and the "actual location". Your memory > buffer isn't bound to a specific location by default. But Linux has to > allocate it somewhere. So your buffer is "located" in some node after > the allocation, but it is not "bound" there (what get_area_membind > returns) which means Linux could have allocated it somewhere else. > > hwloc cannot currently return the "location" of a memory buffer. I > have been thinking about adding this feature in the past, but it looks > like you are the first actual user requesting this. We could add > something like > hwloc_get_last_memory_location(topology, input buffer, outputnodeset) > At least on Linux that's possible. > > For clarity, this is similar to the difference between > hwloc_get_cpubind() and hwloc_get_last_cpu_location(): A task always > runs on a specific PU, even if it is not bound to anything specific PU.
By the way, there is already an issue for this: https://github.com/open-mpi/hwloc/issues/97 Feel to comment there. Brice
