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Optimizing-Shadowsocks.md

@@ -6,26 +6,44 @@ On Debian 7:
 Create `/etc/sysctl.d/local.conf` with the following content:
 
 ```
+# max open files
 fs.file-max = 51200
-
+# max read buffer
 net.core.rmem_max = 67108864
+# max write buffer
 net.core.wmem_max = 67108864
+# default read buffer
 net.core.rmem_default = 65536
+# default write buffer
 net.core.wmem_default = 65536
+# max processor input queue
 net.core.netdev_max_backlog = 4096
+# max backlog
 net.core.somaxconn = 4096
 
+# resist SYN flood attacks
 net.ipv4.tcp_syncookies = 1
+# reuse timewait sockets when safe
 net.ipv4.tcp_tw_reuse = 1
+# turn off fast timewait sockets recycling
 net.ipv4.tcp_tw_recycle = 0
+# short FIN timeout
 net.ipv4.tcp_fin_timeout = 30
+# short keepalive time
 net.ipv4.tcp_keepalive_time = 1200
+# outbound port range
 net.ipv4.ip_local_port_range = 10000 65000
+# max SYN backlog
 net.ipv4.tcp_max_syn_backlog = 4096
+# max timewait sockets held by system simultaneously
 net.ipv4.tcp_max_tw_buckets = 5000
+# turn on TCP Fast Open on both client and server side
 net.ipv4.tcp_fastopen = 3
+# TCP receive buffer
 net.ipv4.tcp_rmem = 4096 87380 67108864
+# TCP write buffer
 net.ipv4.tcp_wmem = 4096 65536 67108864
+# turn on path MTU discovery
 net.ipv4.tcp_mtu_probing = 1
 
 # for high-latency network