Re: My DataBase can't accept conntecion

In response to zab08 <zab08(at)126(dot)com>:

> we have e test db server, we use jdbc to contect.
> but after a whie, The test db server can not accept connect.
>
>
> useps aux | grep postgrescommand :
> postgres 16904 0.0 0.0 46036 3948 ? S 17:03 0:00 /usr/local/pgsql/bin/postgres -D /usr/local/pgsql/data
> postgres 16906 0.0 0.0 46144 2192 ? Ss 17:03 0:00 postgres: writer process
> postgres 16907 0.0 0.0 46036 1088 ? Ss 17:03 0:00 postgres: wal writer process
> postgres 16908 0.0 0.0 46840 2072 ? Ss 17:03 0:00 postgres: autovacuum launcher process
> postgres 16909 0.0 0.0 14248 1012 ? Ss 17:03 0:00 postgres: stats collector process
> postgres 16910 0.0 0.0 46972 2992 ? Ss 17:03 0:00 postgres: postgres edu 172.29.0.40(40608) idle
> postgres 16911 0.0 0.0 46708 2656 ? Ss 17:03 0:00 postgres: postgres edu 172.29.0.40(40609) idle
> postgres 16912 0.0 0.0 46708 2628 ? Ss 17:03 0:00 postgres: postgres edu 172.29.0.40(40610) idle
> postgres 16913 0.0 0.0 46708 2628 ? Ss 17:03 0:00 postgres: postgres edu 172.29.0.40(40611) idle
> postgres 16914 0.0 0.0 46708 2632 ? Ss 17:03 0:00 postgres: postgres edu 172.29.0.40(40612) idle
> postgres 16915 0.0 0.0 46708 2636 ? Ss 17:03 0:00 postgres: postgres edu 172.29.0.40(40613) idle
> postgres 16916 0.0 0.0 46708 2632 ? Ss 17:03 0:00 postgres: postgres edu 172.29.0.40(40614) idle
> postgres 16917 0.0 0.1 47088 4136 ? Ss 17:03 0:00 postgres: postgres edu 172.29.0.40(40615) idle
> postgres 16918 0.0 0.1 47060 4236 ? Ss 17:03 0:00 postgres: postgres edu 172.29.0.40(40616) idle
> postgres 16919 0.0 0.1 47052 4136 ? Ss 17:03 0:02 postgres: postgres edu 172.29.0.40(40617) idle
> postgres 21619 0.0 0.0 46708 2636 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38803) idle
> postgres 21620 0.0 0.0 46708 2636 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38804) idle
> postgres 21621 0.0 0.0 46708 2640 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38805) idle
> postgres 21622 0.0 0.0 46708 2644 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38806) idle
> postgres 21623 0.0 0.0 46708 2644 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38807) idle
> postgres 21624 0.0 0.0 46708 2636 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38808) idle
> postgres 21625 0.0 0.0 46708 2640 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38809) idle
> postgres 21626 0.0 0.0 46708 2644 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38810) idle
> postgres 21627 0.0 0.0 46708 2640 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38811) idle
> postgres 21628 0.0 0.1 47104 4836 ? Ss 19:43 0:00 postgres: postgres edu 172.29.0.40(38812) INSERT
> ...
>
>
> kill -9 pidcommand to kill all of them in the past? and the test db server is shut down.

Are you insane? If your car doesn't start do you throw hand grenades at
it? What you're doing is an excellent way to corrupt the data in your
database.

Use pg_ctl to stop/start/restart the database -- or better, use whatever
tool is provided by your distribution/operating system.

> how to analyze the reason of these? and how to solve?

Have you ever considered looking in the PostgreSQL log files? If I had
to make a guess, I would suspect that you've got the connection limit too
low for the number of connections required by whatever you're doing and
a simple bump of the config parameter will fix the problem. More serious
issues are possible, such as client programs going idle and never releasing
the connection, but I wouldn't assume such problems until you have
evidence.

--
Bill Moran
http://www.potentialtech.com
http://people.collaborativefusion.com/~wmoran/