Increase initcwnd on DebianIn case of high latency link, a too small initcwnd could degrade performance, as it may take a while for throughput to increase to its maximum.
Increasing initcwnd could mitigate this a bit.
Major CDNs are also using a custom initcwnd for better performance.
I used a script from serverfault, did some minor changes, and put it into /etc/network/if-up.d/initcwnd to persist the change:
1234567 #!/bin/bashset -e DEFAULT_ROUTE=`ip route | grep "^default" | head -1`if [ ! -z "$DEFAULT_ROUTE" ]; then ip route change $DEFAULT_ROUTE initcwnd 64fi
Don’t forget to chmod +x it to make it executable.
The change could be verified by:
12 # ip route showdefault via 10.0.0.1 dev eth0 initcwnd 64
In case of high latency link, a too small initcwnd could degrade performance, as it may take a while for throughput to increase to its maximum.
Increasing initcwnd could mitigate this a bit.
Major CDNs are also using a custom initcwnd for better performance.
I used a script from serverfault, did some minor changes, and put it into /etc/network/if-up.d/initcwnd to persist the change:
1 2 3 4 5 6 7 | #!/bin/bash set -e DEFAULT_ROUTE=`ip route | grep "^default" | head -1` if [ ! -z "$DEFAULT_ROUTE" ]; then ip route change $DEFAULT_ROUTE initcwnd 64 fi |
Don’t forget to chmod +x it to make it executable.
The change could be verified by:
1 2 | # ip route show default via 10.0.0.1 dev eth0 initcwnd 64 |