[petsc-users] Understanding streams test on AMD EPYC 7502

[Blaise A Bourdin]

Hi,

I am test-driving hardware for a new machine for my group and having a hard time making sense the output of the stream test:

I am attaching the results and my reference (xeon 8260 nodes on QueenBee 3 at LONI).

If I understand correctly, on the AMD node, the memory bandwidth is saturated with a single core. Is this expected?
The comparison is not totally fair in that QB3 uses intel MPI and MPI compilers, whereas the AMD node uses mvapich2, which I compiled with the following options: ./configure --prefix=/home/amduser/Development/mvapich2-2.3.5-gcc9.3 --with-device=ch3:nemesis:tcp --with-rdma=gen2 --enable-cxx --enable-romio --enable-fast=all --enable-g=dbg --enable-shared-libs=gcc --enable-shared

Am I doing something wrong on the AMD node?

Regards,
Blaise




--
A.K. & Shirley Barton Professor of  Mathematics
Adjunct Professor of Mechanical Engineering
Adjunct of the Center for Computation & Technology
Louisiana State University, Lockett Hall Room 344, Baton Rouge, LA 70803, USA
Tel. +1 (225) 578 1612, Fax  +1 (225) 578 4276 Web http://www.math.lsu.edu/~bourdin

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