因为我在root下下载的postgresql，之后将其安装之类的，创建了用户名postgres,再把权限给了postgres,之后启动数据库发现有问题，一直无法启动数据库，后来pg_ctl start 启动的时候发现/tmp的权限不够，改了权限就好了。
启动前：

启动后：

问题：pg启动异常could not open lock file “/tmp/.s.PGSQL.5432.lock”:

修改tmp权限，chown -R postgres:postgres /tmp

启动成功。

参考文档：

https://blog.51cto.com/bilibili/1969436

出的错：

[postgres@localhost postgresql]$ pg_ctl start -l /usr/local/postgresql/log/pg_server.log
waiting for server to start… stopped waiting
pg_ctl: could not start server
Examine the log output.
[postgres@localhost postgresql]$ pg_ctl start
waiting for server to start…2021-04-01 13:57:03.968 CST [20882] LOG: starting PostgreSQL 13.1 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-4), 64-bit
2021-04-01 13:57:03.969 CST [20882] LOG: listening on IPv6 address “::1”, port 5432
2021-04-01 13:57:03.969 CST [20882] LOG: listening on IPv4 address “127.0.0.1”, port 5432
2021-04-01 13:57:03.970 CST [20882] FATAL: could not open lock file “/tmp/.s.PGSQL.5432.lock”: 权限不够
2021-04-01 13:57:03.972 CST [20882] LOG: database system is shut down
stopped waiting
pg_ctl: could not start server
Examine the log output.
[postgres@localhost postgresql]$ su
密码：
[root@localhost postgresql]# chown -R postgres:postgres /tmp
[root@localhost postgresql]# su postgres
[postgres@localhost postgresql]$ pg_ctl start -l /usr/local/postgresql/log/pg_server.log
waiting for server to start… done
server started
[postgres@localhost postgresql]$ psql
psql (13.1)
成功了。

[postgres@localhost postgresql]$ cat data/postgresql.conf | grep unix_socket_directories
#unix_socket_directories = ‘/tmp’ # comma-separated list of directories

参考链接：

https://blog.csdn.net/huguangshanse00/article/details/40413549?locationNum=5