hi sven,
i try at the moment to figure out why our QDR Infiniband is not
as fast as it should be. So I realized that we use 2k mtu size, and
tried to change this to 4k. But don't now how.
how fast are you expecting to get? (and what are you measuring)
enviroment:
mellanox connectX-3 cards in interlagos machine with sl6.3 64 bit
(RHEL/SL Ofed stack)
interlagos as in AMD RD890 IO bridge that only has max pcie payload of
128byte and thus can only reach 75% of a pcie-2 link (which will result
in approx 75% of the QDR link)
(google pcie payload plxtech, theres a pdf soemwhere with a self
explaining plot)
very nice of amd not to have pcie-3 chips ...
stijn
mellanox sx6036 switch (4k mtu enabled)
in the mellanox docu i found something about a module parameter
"set_4k_mtu" but this don't work with SL6.3 (unknown parameter)
this also don't work, because there is no "mlx4_port1_mtu"
echo 4096 > /sys/class/infiniband/mlx4_0/device/mlx4_port1_mtu
is it possible that the sl mellanox module don't support 4k mtu?
best regards
sven
