$cat /proc/sys/net/ipv4/tcp_mem 40704 54272 81408 $ tcp_mem vector of 3 INTEGERs: min, pressure, max min: below this number of pages TCP is not bothered about its memory appetite. pressure: when amount of memory allocated by TCP exceeds this number of pages, TCP moderates its memory consumption and enters memory pressure mode, which is exited when …
Tag Archives: tcp
remembered connection requests .. syn .. backlog
$cat /proc/sys/net/ipv4/tcp_max_syn_backlog 1024 $ Maximal number of remembered connection requests, which still did not receive an acknowledgement from connecting client. The default value is 1024 for systems with more than 128 MB of memory, and 128 for low memory machines. If server suffers of overload, try to increase this number. source : http://www.linuxinsight.com/proc_sys_net_ipv4_tcp_max_syn_backlog.html Script.January/HPUX11/GEN003600 – …
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tcp latency….throughput..
$cat /proc/sys/net/ipv4/tcp_low_latency 0 $ tcp_low_latency – BOOLEAN If set, the TCP stack makes decisions that prefer lower latency as opposed to higher throughput. By default, this option is not set meaning that higher throughput is preferred. An example of an application where this default should be changed would be a Beowulf compute cluster. Default: 0 …
the interval between the last data packet sent and…
$cat /proc/sys/net/ipv4/tcp_keepalive_time 7200 $ tcp_keepalive_time the interval between the last data packet sent (simple ACKs are not considered data) and the first keepalive probe; after the connection is marked to need keepalive, this counter is not used any further source :http://tldp.org/HOWTO/TCP-Keepalive-HOWTO/usingkeepalive.html linux/net/ipv4/tcp.c – 8 identical 365: * TCP Keep-Alives (4.2.3.6) 366: * MAY provide keep-alives. …
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What does rfc 1337 say ?
From RFC 1337. TIME-WAIT state removes the hazard of old duplicates for “fast” or “long” connections, in which clock-driven ISN selection is unable to prevent overlap of the old and new sequence spaces. The TIME-WAIT delay allows all old duplicate segments time enough to die in the Internet before the connection is reopened. echo 1 …
tcp tuning tcp_rfc1337
From RFC 1337. TIME-WAIT state removes the hazard of old duplicates for “fast” or “long” connections, in which clock-driven ISN selection is unable to prevent overlap of the old and new sequence spaces. The TIME-WAIT delay allows all old duplicate segments time enough to die in the Internet before the connection is reopened. echo 1 …