Viprion congestion settings with MPLS
We have a Viprion F5 acting as Layer 7 Loadbalancer towards an Apache webserver. We observed download times from our remote locations of 1MB/s (connected with MPLS at 65MB/s, rtt=5ms). Downloading directly from the Apache, our remote sites reach 50MB/s download times. Local (LAN 125MB/s, rtt=2ms) we reach 22MB/s via loadbalancer and 77MB directly from Apache. Even with tcp receive window with auto (130kB), proxy window auto (200kB low, 260kB high) and send window auto (260kB), we did not reach reasonable download times. As workaround we implemented the following irule: if { [TCP::mss] < 1460 } { TCP::congestion bbr } elseif { [TCP::rtt] > 0 && [TCP::rtt] < 100 } { TCP::congestion highspeed } elseif { [IP::ttl] > 250 } { TCP::congestion highspeed } else { TCP::congestion bbr } } With that, local and remote are now around 20-25MB/s Is this normal or do we suffer from some other issues around the F5? Why do we need those congestion settings whereas a standard Apache is in all cases better?