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Modifying Network Parameters

Purpose

Modify some parameter settings at the operating system layer to improve server performance.

Procedure

Linux Parameter

Description

Operation

tcp_max_syn_backlog

Maximum number of clients that can receive SYN (synchronization) packets. Default value: 2048; recommended value: 8192

echo 8192 > /proc/sys/net/ipv4/

tcp_max_syn_backlog

net.core.somaxconn

Maximum number of clients that can process data in the server, that is, the maximum number of connections. Default value: 128; recommended value: 1024

echo 1024 > /proc/sys/net/core/somaxconn

net.core.rmem_max

Maximum size of the socket receive buffer. Default value: 229376; recommended value: 16777216

echo 16777216 > /proc/sys/net/core/rmem_max

net.core.wmem_max

Maximum size (in bytes) of the socket transmit buffer. Default value: 229376; recommended value: 16777216

echo 16777216 > /proc/sys/net/

core/wmem_max

net.ipv4.tcp_rmem

Size of the read buffer. The three numbers indicate the minimum, default, and maximum size of the read buffer, respectively. Default value: 4096 87380 6291456; recommended value: 4096 87380 16777216.

echo "4096 87380 16777216"

> /proc/sys/net/ipv4/tcp_rmem

net.ipv4.tcp_wmem

Size of the write buffer. The three numbers indicate the minimum, default, and maximum size of the write buffer, respectively. Default value: 4096 16384 4194304; recommended value: 4096 65536 16777216.

echo "4096 65536 16777216"

> /proc/sys/net/ipv4/tcp_wmem

net.ipv4.max_tw_buckets

Maximum number of TIME_WAIT sockets that can be retained by the system at the same time. Default value: 2048; recommended value: 360000.

echo 360000 > /proc/sys/net/ipv4/tcp_max_tw_buckets