User Manual

Rev 2.2-1.0.1
Mellanox Technologies
279
9.5.5 ib_write_bw
ib_write_bw calculates the BW of RDMA write between a pair of machines. One acts as a server
and the other as a client. The client RDMA writes to the server memory and calculate the BW by
sampling the CPU each time it receive a successful completion. The test supports features such as
Bidirectional, in which they both RDMA write to each other at the same time, change of mtu
size, tx size, number of iteration, message size and more. Using the "-a" flag provides results for
all message sizes.
more. Using the "-a" provides results for all message sizes.
Synopsis
Server
ib_write_bw [options]
Client
ib_write_bw [options] <hostname>
Options
The table below lists the various flags of the command.
--output=<units> Set verbosity output level: bandwidth , message_rate,
latency_typical
--pkey_index=<pkey index> PKey index to use for QP
Table 53 - ib_write_bw Flags and Options
Flag Description
-a, --all Run sizes from 2 till 2^23
-b, --bidirectional Measure bidirectional bandwidth (default unidirectional)
-c, --connection=<RC/XRC/UC/
DC>
Connection type RC/XRC/UC/DC (default RC)
-d, --ib-dev=<dev> Use IB device <dev> (default first device found)
-D, --duration Run test for a customized period of seconds.
-f, --margin Measure results within margins. (default=2sec)
-F, --CPU-freq Do not fail even if cpufreq_ondemand module is loaded
-h, --help Show this help screen.
-i, --ib-port=<port> Use port <port> of IB device (default 1)
-I, --inline_size=<size> Max size of message to be sent in inline
Table 52 - Additional ib_send_lat Flags and Options
Flag Description