User Manual

InfiniBand FabricRev 4.3
Mellanox Technologies
81
7.4.5.1 ib_write_bw Synopsys
7.4.5.2 ib_write_bw Options
The table below lists the various flags of the command.
7.4.6 ib_write_lat
ib_write_lat calculats the latency of RDMA write operation of message_sizeB between a pair of
machines. One acts as a server and the other as a client. They perform a ping pong benchmark on
which one side RDMA writes to the other side memory only after the other side wrote on his
memory. Each of the sides samples the CPU clock each time they write to the other side memory,
in order to calculate latency.
ib_write_bw [-q num of qps] [-c(onnection_type) RC\UC\UD] [-i(b_port) ib_port] [-
m(tu) mtu_size] [-s(ize) message_size] [-t(x-depth) tx_size] [-n iteration_num] [-
p(ort) PDT_port] [-b(idirectional)] [-a(ll)] [-V(ersion)]
Table 22 - ib_write_bw Flags and Options
Flag Description
-p, --port=<port> Listens on/connect to port <port> (default 18515)
-d, --ib-dev=<dev> Uses IB device <device guid> (default first device found)
-i, --ib-port=<port> Uses port <port> of IB device (default 1)
-m, --mtu=<mtu> The mtu size (default 1024)
-c, --connection=<RC/UC> Connection type RC/UC/UD (default RC)
-s, --size=<size> The size of message to exchange (default 65536)
-a, --all Runs sizes from 2 till 2^23
-t, --tx-depth=<dep> The size of tx queue (default 100)
-n, --iters=<iters> The number of exchanges (at least 2, default 1000)
-b, --bidirectional Measures bidirectional bandwidth (default unidirectional)
-V, --version Displays version number
-o, --post=<num of posts> The number of posts for each qp in the chain (default tx_depth)
-q, --qp=<num of qp's> The number of qp's(default 1)
-g, --grh Use GRH with packets (mandatory for RoCE)