tcp建连优化
1 tcp建连，降低客户端超时时间
net.ipv4.tcp_syn_retries = 6
2 tcp建连，服务端避免syn攻击
netstat -s | grep “SYNs to LISTEN” 1192450 SYNs to LISTEN sockets dropped
可以考虑增大syn队列
net.ipv4.tcp_max_syn_backlog = 1024
超过上述队列后，启用syn cookie
net.ipv4.tcp_syncookies =[……]
官方权威指南：https://www.oracle.com/cn/technical-resources/articles/java/g1gc.html[……]
log4j:WARN No appenders could be found for logger (org.apache.hadoop.metrics2.lib.MutableMetricsFactory).
log4j:WARN Please initialize the log4j system properly.
解决方法：src/main/resources下添加log4j.properties
# Set root logger level to DEBUG and its o[……]
服务端性能压测时，在客户端侧经常遇到两个问题：
可以通过docker的方式，突破这两个限制
#!/bin/bash
docker run -v $(pwd):/benchmark-client.bin -it ubuntu:20.04 /app/benchmark-client.bin
如上，我们启用若干个个docker，每个都[……]