| /sysctl/50-net.conf |
|---|
| @@ -0,0 +1,60 @@ |
|---|
| # Default: cubic |
| net.ipv4.tcp_congestion_control=htcp |
| |
| # CoDel (Default: pfifo_fast) |
| # https://lwn.net/Articles/616241/ |
| net.core.default_qdisc=fq_codel |
| |
| # Default: 32768 60999 |
| net.ipv4.ip_local_port_range=1025 65535 |
| |
| # TCP window scaling tries to avoid saturating the network adapter with |
| # incoming packets. |
| net.ipv4.tcp_window_scaling = 1 |
| |
| # If enabled, assume that no receipt of a window-scaling option means that |
| # the remote TCP is broken and treats the window as a signed quantity. If |
| # disabled, assume that the remote TCP is not broken even if we do not |
| # receive a window scaling option from it. |
| net.ipv4.tcp_workaround_signed_windows = 1 |
| |
| # RFC 1337, TIME-WAIT Assassination Hazards in TCP, a fix written in 1992 |
| # for some theoretically-possible failure modes for TCP connections. To |
| # this day this RFC still has people confused if it negatively impacts |
| # performance or not or is supported by any decent router. Murphy's Law is |
| # that the only router that it would even have trouble with, is most likely |
| # your own. |
| net.ipv4.tcp_rfc1337 = 1 |
| |
| # TCP SACK and FACK refer to options found in RFC 2018 and are also |
| # documented back to Linux Kernel 2.6.17 with an experimental "TCP-Peach" |
| # set of functions. These are meant to get you your data without excessive |
| # losses. |
| net.ipv4.tcp_sack = 1 |
| net.ipv4.tcp_fack = 1 |
| |
| # RFC 2923 IPv6 uses PMTU by default to avoid segmenting packets at the |
| # router level, but its optional for IPv4. PMTU is meant to inform routers |
| # of the best packet sizes to use between links, but its a common admin |
| # practice to block ICMP ports that allow pinging, thus breaking this |
| # mechanism. Linux tries to use it, and so do I: if you have problems, you |
| # have a problem router, and can change the "no" setting to 1. "MTU probing" |
| # is also a part of this: 1 means try, and 0 means don't. |
| net.ipv4.ip_no_pmtu_disc = 0 |
| net.ipv4.tcp_mtu_probing = 1 |
| |
| # Don't ignore ICMP |
| net.ipv4.icmp_echo_ignore_all=0 |
| net.ipv4.icmp_echo_ignore_broadcasts=0 |
| |
| # Netflix 2014 EC2 sysctl tweaks |
| # http://www.slideshare.net/AmazonWebServices/pfc306-performance-tuning-amazon-ec2-instances-aws-reinvent-2014 |
| net.core.somaxconn=1000 |
| net.core.netdev_max_backlog=5000 |
| net.core.rmem_max=16777216 |
| net.core.wmem_max=16777216 |
| net.ipv4.tcp_wmem=4096 12582912 16777216 |
| net.ipv4.tcp_rmem=4096 12582912 16777216 |
| net.ipv4.tcp_max_syn_backlog=8096 |
| net.ipv4.tcp_slow_start_after_idle=0 |
| net.ipv4.tcp_tw_reuse=1 |
