John, as an aside it is always worth running 'lstopo' from the hwloc
package to look at the layout of your cpus cores and caches.
Getting a bit late now so I apologise for being too lazy to boot up my Pi
to capture the output.
On Wed, 22 Jul 2020 at 19:55, George Bosilca via users <
users@lists.op
John,
There are many things in play in such an experiment. Plus, expecting linear
speedup even at the node level is certainly overly optimistic.
1. A single core experiment has full memory bandwidth, so you will
asymptotically reach the max flops. Adding more cores will increase the
memory pressu
Hi Joseph, JohnThank you for your replies.I’m using Ubuntu 20.04 aarch64 on a 8 x Raspberry Pi 4 cluster.The symptoms I’m experiencing are that the HPL Linpack performance in Gflops increases on a single core as NB is increased from 32 to 256. The theoretical maximum is 6 Gflops per core. I can ach
Glad you figured it out!
I was waiting for Mellanox support to jump in and answer here; I am not part of
the UCX community, so I can't really provide definitive UCX answers.
On Jul 22, 2020, at 1:16 PM, Lana Deere
mailto:lana.de...@gmail.com>> wrote:
Never mind. This was apparently because
Never mind. This was apparently because I had ucx configured for static
libraries while openmpi was configured for shared libraries.
.. Lana (lana.de...@gmail.com)
On Tue, Jul 21, 2020 at 12:58 PM Lana Deere wrote:
> I'm using the infiniband drivers in the CentOS7 distribution, not the
> Me
Hi John,
Depending on your platform the default behavior of Open MPI is to mmap a
shared backing file that is either located in a session directory under
/dev/shm or under $TMPDIR (I believe under Linux it is /dev/shm). You
will find a set of files there that are used to back shared memory. Th
Hi
I’m trying to investigate an HPL Linpack scaling issue on a single node,
increasing from 1 to 4 cores.
Regarding single node messages, I think I understand that Open-MPI will select
the most efficient mechanism, which in this case I think should be vader shared
memory.
But when I run Linpa
