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Firefishy/sysctl-tune.conf

Created March 23, 2017 17:57
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Safe sysctl tuning for modern high traffic systems
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sysctl-tune.conf
# Enable Packetization Layer Path MTU Discovery.
net.ipv4.tcp_mtu_probing = 1
net.ipv4.tcp_base_mss = 1024
# Ensure slow start is disabled
# https://github.com/ton31337/tools/wiki/tcp_slow_start_after_idle---tcp_no_metrics_save-performance
net.ipv4.tcp_slow_start_after_idle = 0
net.ipv4.tcp_no_metrics_save = 0
# Tune network buffers - servers have more than 16MB of RAM in 2017
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216
@jult
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jult commented Apr 24, 2018

Those rmem and wmem values cause bufferbloat.
Also consider changing to fq_codel; https://lwn.net/Articles/616241/
Here's my sysctl.conf; https://gist.github.com/jult/19decfc31ffae0b2b3fa4d48e2ffdd9f

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