- Red Hat Enterprise Linux 6, 7, 8
- How to use
qperfto measure network bandwidth and latency performance?
- Is there a supported alternative to
iperfto measure network throughput?
- How do I test performance of RDMA?
qperf from the RHEL server channel on both the qperf Server and qperf Client:
[root@yourQperfServer ~]# yum install qperf [root@yourQperfClient ~]# yum install qperf
Checking for Bandwidth
Server (Receiving Data)
Have one system listen as a qperf server:
[root@yourQperfServer ~]# qperf
The server listens on TCP Port 19765 by default. This can be changed with the
This port will need to be allowed in any firewall present. On iptables:
[root@yourQperfServer ~]# iptables -I INPUT -m tcp -p tcp --dport 19765 -j ACCEPT && iptables -I INPUT -m tcp -p tcp --dport 19766 -j ACCEPT
Or on firewalld, 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.
[root@yourQperfServer ~]# firewall-cmd --permanent --add-port=19765/tcp --add-port=19766/tcp success [root@yourQperfServer ~]# firewall-cmd --reload success [root@yourQperfServer ~]#firewall-cmd --list-all public (active) target: default icmp-block-inversion: no interfaces: enp0s25 sources: services: ssh dhcpv6-client http https ports: 19765/tcp 19766/tcp protocols: masquerade: no forward-ports: source-ports: icmp-blocks: rich rules:
Have the other system connect to qperf server as a client:
[root@yourQperfClient ~]# qperf -ip 19766 -t 60 --use_bits_per_sec <server hostname or ip address> tcp_bw
Results are printed on the client only, the following result shows throughput between these two systems is 16.1 gigabit per second:
tcp_bw: bw = 16.1 Gb/sec
--use_bits_per_sec option is not used, the throughput is supplied in GiB per second (or other applicable IEC binary unit):
tcp_bw: bw = 1.94 GB/sec
Checking for latency
[root@yourQperfClient ~]# qperf -vvs <server hostname or ip address> tcp_lat
Results are printed on the client only, the following result shows latency value is
311 Microseconds and then there are few other details as well.
loc_xx shows details from local system perspective and
rem_xx shows the same from remote system perspective. Refer
man qperf for more options / verbosity.
tcp_lat: latency = 311 us msg_rate = 3.22 K/sec loc_send_bytes = 3.22 KB loc_recv_bytes = 3.22 KB loc_send_msgs = 3,218 loc_recv_msgs = 3,217 rem_send_bytes = 3.22 KB rem_recv_bytes = 3.22 KB rem_send_msgs = 3,217 rem_recv_msgs = 3,217
Other tests are available, including UDP bandwidth and latency, SCTP bandwidth and latency, and other protocols which run on RDMA.
TESTS section of
man qperf for more details.
- qperf is a network bandwidth and latency measurement tool which works over many transports including TCP/IP, RDMA, UDP, and SCTP.
- Red Hat Enterprise Linux
- Learn more
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