redis啟動時，提示信息如下：
>>> redis-server
# oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
# Redis version=4.0.9, bits=64, commit=00000000, modified=0, pid=23974, just started
# Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf
* Increased maximum number of open files to 10032 (it was originally set to 1024).
# Creating Server TCP listening socket *:6379: bind: Address already in use
原因：
是因為linux中已經(jīng)啟動redis.
解決辦法：
第一種（最簡單）：
>>> /etc/init.d/redis-server stop
[ ok ] Stopping redis-server (via systemctl): redis-server.service.
更多關(guān)于redis命令：http://www.chenxm.cc/post/548.html
第二種方法：
找到redis-server的進程，然后殺死對應(yīng)的進程，然后重新啟動redis
>>> ps -ef | grep -i redis
root 3585 19590 0 10:36 pts/20 00:00:00 redis-server *:6379
user 3684 3663 0 10:38 pts/21 00:00:00 grep --color=auto -i redis
進程3585是redis的服務(wù)，
kill -9 3585
啟動redis服務(wù)
>>> redis-server
# oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
# Redis version=4.0.9, bits=64, commit=00000000, modified=0, pid=3585, just started
# Warning: no config file specified, using the default config. In order to specify a config file use redis-server /path/to/redis.conf
* Increased maximum number of open files to 10032 (it was originally set to 1024).
_._
_.-``__ ''-._
_.-`` `. `_. ''-._ Redis 4.0.9 (00000000/0) 64 bit
.-`` .-```. ```\/ _.,_ ''-._
( ' , .-` | `, ) Running in standalone mode
|`-._`-...-` __...-.``-._|'` _.-'| Port: 6379
| `-._ `._ / _.-' | PID: 3585
`-._ `-._ `-./ _.-' _.-'
|`-._`-._ `-.__.-' _.-'_.-'|
| `-._`-._ _.-'_.-' | http://redis.io
`-._ `-._`-.__.-'_.-' _.-'
|`-._`-._ `-.__.-' _.-'_.-'|
| `-._`-._ _.-'_.-' |
`-._ `-._`-.__.-'_.-' _.-'
`-._ `-.__.-' _.-'
`-._ _.-'
`-.__.-'
# WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.
# Server initialized
# 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.
# 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.
* Ready to accept connections
