Using qperf to measure network bandwidth and latency

qperf is a network bandwidth and latency measurement tool which works over many transports including TCP/IP, RDMA, UDP and SCTP

Step 1: Installing qperf on both Server and Client

Server> # yum install qperf
Client> # yum install qperf

Step 2: Open Up the Firewall on the Server

# firewall-cmd --permanent --add-port=19765-19766/tcp
# firewall-cmd --reload

The Server listens at TCP Port 19765 by default. Do note that once qperf makes a connection, it will create a control port and data port , the default data port is 19765 but we also need to enable a data port to run test which can be 19766.

Step 3a: Have the Server listen (as qperf server)

Server> $ qperf

Step 4: Connect to qperf Server with qperf Client and measure bandwidth

Client > $ qperf -ip 19766 -t 60 qperf_server_ip_address tcp_bw
    bw  =  2.52 GB/sec

Step 5: Connect to qperf Server with qperf Client and measure latency

qperf -vvs qperf_server_ip_address tcp_lat
latency = 20.7 us
msg_rate = 48.1 K/sec
loc_send_bytes = 48.2 KB
loc_recv_bytes = 48.2 KB
loc_send_msgs = 48,196
loc_recv_msgs = 48,196
rem_send_bytes = 48.2 KB
rem_recv_bytes = 48.2 KB
rem_send_msgs = 48,197
rem_recv_msgs = 48,197


  1. How to use qperf to measure network bandwidth and latency performance?