09/23/13

linux的tcp调优

kernel.shmall = 268435456

net.ipv4.tcp_syncookies = 1

net.ipv4.tcp_tw_reuse = 1

net.ipv4.tcp_tw_recycle = 1

net.ipv4.tcp_fin_timeout = 30

net.ipv4.tcp_keepalive_time = 1200

net.ipv4.ip_local_port_range = 1024 65000

net.ipv4.tcp_max_tw_buckets = 5000

net.ipv4.tcp_max_tw_buckets = 5000

net.ipv4.tcp_fin_timeout = 30

net.ipv4.tcp_keepalive_time = 300

net.ipv4.tcp_syncookies = 1

net.ipv4.tcp_tw_reuse = 1

net.ipv4.tcp_tw_recycle = 1

net.ipv4.ip_local_port_range = 5000 65000

net.ipv4.tcp_mem = 786432 1048576 1572864

net.core.wmem_max = 873200

net.core.rmem_max = 873200

net.ipv4.tcp_wmem = 8192 436600 873200

net.ipv4.tcp_rmem = 32768 436600 873200

net.core.somaxconn = 256

net.core.netdev_max_backlog = 1000

net.ipv4.tcp_max_syn_backlog = 2048

net.ipv4.tcp_retries2 = 5

net.ipv4.tcp_keepalive_time = 500

net.ipv4.tcp_keepalive_intvl = 30

net.ipv4.tcp_keepalive_probes = 3

net.ipv4.conf.lo.arp_ignore = 0

net.ipv4.conf.lo.arp_announce = 0

net.ipv4.conf.all.arp_ignore = 0

net.ipv4.conf.all.arp_announce = 0

net.ipv4.tcp_syncookies = 1

#表示开启SYN Cookies。当出现SYN等待队列溢出时,启用cookies来处理,可防范少量SYN攻击,默认为0,表示关闭;

net.ipv4.tcp_tw_reuse = 1

#表示开启重用。允许将TIME-WAIT sockets重新用于新的TCP连接,默认为0,表示关闭;

net.ipv4.tcp_tw_recycle = 1

#表示开启TCP连接中TIME-WAIT sockets的快速回收,默认为0,表示关闭。

net.ipv4.tcp_fin_timeout = 30

#表示如果套接字由本端要求关闭,这个参数决定了它保持在FIN-WAIT-2状态的时间。

net.ipv4.tcp_keepalive_time = 1200

#表示当keepalive起用的时候,TCP发送keepalive消息的频度。缺省是2小时,改为20分钟。

net.ipv4.ip_local_port_range = 1024 65000

#表示用于向外连接的端口范围。缺省情况下很小:32768到61000,改为1024到65000。

net.ipv4.tcp_max_tw_buckets = 5000

#表示系统同时保持TIME_WAIT套接字的最大数量,如果超过这个数字,

#TIME_WAIT套接字将立刻被清除并打印警告信息。默认为180000,改为5000。

#对于Apache、Nginx等服务器,上几行的参数可以很好地减少TIME_WAIT套接字数量,

#但是对于Squid,效果却不大。此项参数可以控制TIME_WAIT套接字的最大数量,避免Squid服务器被大量的TIME_WAIT套接字拖死。