I found there are still failed request when the traffic is high using command like this "haproxy -f /etc/haproxy.cfg -p /var/run/haproxy.pid -sf $(cat /var/run/haproxy.pid)" to hot reload the updated config file.
Here below is the presure testing result using webbench : /usr/local/bin/webbench -c 10 -t 30 http://targetHAProxyIP:1080/<http://targethaproxyip:1080/> Webbench - Simple Web Benchmark 1.5 Copyright (c) Radim Kolar 1997-2004, GPL Open Source Software. Benchmarking: GET http://targetHAProxyIP:1080/<http://targethaproxyip:1080/> 10 clients, running 30 sec. Speed=70586 pages/min, 13372974 bytes/sec. * Requests: 35289 susceed, 4 failed.* I run command "haproxy -f /etc/haproxy.cfg -p /var/run/haproxy.pid -sf $(cat /var/run/haproxy.pid)" several times during the pressure testing. In the haproxy documentation, it mentioned "They will receive the SIGTTOU 611 signal to ask them to temporarily stop listening to the ports so that the new 612 process can grab them", * so there might be a time period that the old process is not listening on the PORT(say 80) and the new process haven't start to listen to the PORT (say 80), and during this specific time period, it will cause the NEW connections failed, make sense?*
