c1000k TCP 连接上限测试1

启动服务

指定一个空闲端口，服务端会顺次打开100个端口进行监听，并且在当前terminal挂起

[[email protected] c1000k-master]# ./server  8000
server listen on port: 8000
server listen on port: 8001
server listen on port: 8002
server listen on port: 8003
server listen on port: 8004
server listen on port: 8005
server listen on port: 8006
server listen on port: 8007
server listen on port: 8008
server listen on port: 8009
server listen on port: 8010
server listen on port: 8011
server listen on port: 8012
server listen on port: 8013
server listen on port: 8014
server listen on port: 8015
server listen on port: 8016
server listen on port: 8017
server listen on port: 8018
server listen on port: 8019
server listen on port: 8020
server listen on port: 8021
server listen on port: 8022
server listen on port: 8023
server listen on port: 8024
server listen on port: 8025
server listen on port: 8026
server listen on port: 8027
server listen on port: 8028
server listen on port: 8029
server listen on port: 8030
server listen on port: 8031
server listen on port: 8032
server listen on port: 8033
server listen on port: 8034
server listen on port: 8035
server listen on port: 8036
server listen on port: 8037
server listen on port: 8038
server listen on port: 8039
server listen on port: 8040
server listen on port: 8041
server listen on port: 8042
server listen on port: 8043
server listen on port: 8044
server listen on port: 8045
server listen on port: 8046
server listen on port: 8047
server listen on port: 8048
server listen on port: 8049
server listen on port: 8050
server listen on port: 8051
server listen on port: 8052
server listen on port: 8053
server listen on port: 8054
server listen on port: 8055
server listen on port: 8056
server listen on port: 8057
server listen on port: 8058
server listen on port: 8059
server listen on port: 8060
server listen on port: 8061
server listen on port: 8062
server listen on port: 8063
server listen on port: 8064
server listen on port: 8065
server listen on port: 8066
server listen on port: 8067
server listen on port: 8068
server listen on port: 8069
server listen on port: 8070
server listen on port: 8071
server listen on port: 8072
server listen on port: 8073
server listen on port: 8074
server listen on port: 8075
server listen on port: 8076
server listen on port: 8077
server listen on port: 8078
server listen on port: 8079
server listen on port: 8080
server listen on port: 8081
server listen on port: 8082
server listen on port: 8083
server listen on port: 8084
server listen on port: 8085
server listen on port: 8086
server listen on port: 8087
server listen on port: 8088
server listen on port: 8089
server listen on port: 8090
server listen on port: 8091
server listen on port: 8092
server listen on port: 8093
server listen on port: 8094
server listen on port: 8095
server listen on port: 8096
server listen on port: 8097
server listen on port: 8098
server listen on port: 8099

运行客户端

[[email protected] c1000k-master]# ./client 127.0.0.1 8000
connections: 922
error: Connection refused
[[email protected] c1000k-master]# 

运行完服务端也会跟着退出

...
...
server listen on port: 8095
server listen on port: 8096
server listen on port: 8097
server listen on port: 8098
server listen on port: 8099
connections: 921
error: Too many open files
[[email protected] c1000k-master]# 

结果分析

客户端反馈结果

connections: 922
error: Connection refused

说明客户端的第922个连接被拒绝了

服务端反馈结果

connections: 921
error: Too many open files

说明服务端只能打开921个连接，无法打开更多，触及了 max-open-files 规定的上限，所以退出了

原文地址