Are this network settings good for a router?

robertjinx · 08-04-2012, 01:55 PM

Hello, I've got a small router which I use at home. The router is connected to the internet using a ADSL modem and a second adapter for the internal network, to spread the "internet" around

Here is what I use to tune the network:

Code:

net.ipv4.tcp_congestion_control = cubic
net.ipv4.ip_forward = 1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_fin_timeout = 30
net.ipv4.tcp_keepalive_intvl = 30
net.ipv4.tcp_keepalive_probes = 5
net.ipv4.tcp_keepalive_time = 600
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_timestamps = 0
net.ipv4.tcp_sack = 1
net.ipv4.tcp_no_metrics_save = 1
net.core.netdev_max_backlog = 3000
net.core.somaxconn = 2048
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 87380 16777216

My question is: Are this settings good, mainly because I'm watching online TV using http://sopcast.com/ and a lot of Youtube.
I'm not a network guy, but for me they seem good, but I could be wrong.

unSpawn · 08-05-2012, 09:51 AM

Quote:

Originally Posted by robertjinx

Are this settings good

Especially as engineer you should appreciate Linux comes with full documentation and that about any condition you can think up can be tested. If you based your settings on
0) having read what's available in /usr/src/linux.*/Documentation/network.*/,
1) having noted defaults before making changes,
2) not having based any changes on outdated HOWTO's littering the 'net or any "HOWTO's" that offer sysctl settings but w/o explaining them (that'll be most and esp. web blog posts are particularly useless) and
3) having tested (Iperf?) the difference wrt resource usage (Linux does rmem / wmem autotuning), HTCP (older 2.6 kernels) vs BIC, .*ACK settings, timeouts and time stamps wrt connection build / teardown and speed, etc, etc then you've got objective results. Measuring things well means a label "good" makes sense or not.