临时解决办法：
echo 511 > /proc/sys/net/core/somaxconn
永久解决办法
vi /etc/sysctl.conf
在里面添加net.core.somaxconn= 1024 然后执行sysctl -p 就可以永久消除这个warning
问题二：
WARNING overcommit_memory is set to 0! Background save may fail under low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.
可以参考问题一的解决
问题三：
WARNING you have Transparent Huge Pages (THP) support enabled in your kernel. This will create latency and memory usage issues with Redis. To fix this issue run the command 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' as root, and add it to your /etc/rc.local in order to retain the setting after a reboot. Redis must be restarted after THP is disabled
