February 24, 2012

Lower initial TCP RTO - Redhat kernel patch

I have recently back-ported the rfc2988bis changes (initRTO=1 and fallack) to the redhat 2.6.32 kernel - find the patch on my github account at @ https://github.com/alouche/redhat-2.6.32-kernel-patches/blob/master/rfc2988bis.patch

On short lived connections with a lot of 3WHS, a lower initial RTO will improve 3WHS latency by 2*2000ms*X% (X% being the average of packet drops of a specific route). For further technical details, refer to https://www.ietf.org/proceedings/77/slides/tcpm-1.pdf