<span style="font-family: arial, sans-serif;">Dear AMQPers,</span><div style="font-family: arial, sans-serif;"><br></div><div style="font-family: arial, sans-serif;">I am setting two AMQP message brokers on a LAN running the latest RabbitMQ Server 3.1.3. They will be part of a high-availability cluster with full mirroring. The cluster will receive about 430 messages per second (or 280KB/s incoming data as shown by VM statistics). Each server process will run on its own dedicated VM with 4 CPUs and 8GB of RAM. Some of the publishers are on high-latency WAN connections, while the consumers are primarily located on the LAN.</div><div style="font-family: arial, sans-serif;"><br></div><div style="font-family: arial, sans-serif;">I am considering the following changes:</div><div style="font-family: arial, sans-serif;"><pre style="margin: 1em 1em 1em 1.6em; padding-top: 2px; padding-right: 2px; padding-bottom: 2px; background-color: rgb(250, 250, 250); border: 1px solid rgb(218, 218, 218); width: auto; overflow-x: auto; overflow-y: hidden; color: rgb(72, 72, 72); font-size: 12px;">echo 'net.core.wmem_max=1048576' >> /etc/sysctl.conf
echo 'net.core.rmem_max=1048576' >> /etc/sysctl.conf
echo 'net.ipv4.tcp_rmem= 10240 87380 1048576' >> /etc/sysctl.conf
echo 'net.ipv4.tcp_wmem= 10240 87380 1048576' >> /etc/sysctl.conf
echo 'net.ipv4.tcp_window_scaling = 1' >> /etc/sysctl.conf
echo 'net.ipv4.tcp_timestamps = 1' >> /etc/sysctl.conf
echo 'net.ipv4.tcp_sack = 1' >> /etc/sysctl.conf
echo 'net.ipv4.tcp_no_metrics_save = 1' >> /etc/sysctl.conf
echo 'net.core.netdev_max_backlog = 5000' >> /etc/sysctl.conf</pre></div><div style="font-family: arial, sans-serif;">Please let me know your thoughts on whether I should apply these or other Linux network tweaks, or if it's recommended to go with the OS defaults?</div><div style="font-family: arial, sans-serif;"><br></div><div style="font-family: arial, sans-serif;"><br></div><div style="font-family: arial, sans-serif;">Thanks,</div><div style="font-family: arial, sans-serif;">Donovan</div><div style="font-family: arial, sans-serif;"><br></div>