Thread: Two Postgres master process are showing - one is on and off

Two Postgres master process are showing - one is on and off

From

chiru r

Date:

20 August 2019, 23:32:25

Hi All,

I have observed one of our PostgreSQL DB instance showing two postgres process on Linux server as highlighted. The second postgres process is on and off.

We did not find any references in logs.

Please provide your advice and help on this issue.

DB version : PostgreSQL 9.5.10

Server version : RHEL 7.6

[postgres@PGSERVER data]$ ps -ef|grep postgres

root 5922 5875 0 Jul31 pts/0 00:00:00 sudo su - postgres

root 5927 5922 0 Jul31 pts/0 00:00:00 su - postgres

postgres 5928 5927 0 Jul31 pts/0 00:00:00 -bash

root 11585 11535 0 11:29 pts/2 00:00:00 sudo su - postgres

root 11606 11585 0 11:29 pts/2 00:00:00 su - postgres

postgres 11607 11606 0 11:29 pts/2 00:00:00 -bash

root 17185 17141 0 Aug19 pts/1 00:00:00 sudo su - postgres

root 17189 17185 0 Aug19 pts/1 00:00:00 su - postgres

postgres 17190 17189 0 Aug19 pts/1 00:00:00 -bash

postgres 33438 1 0 12:41 ? 00:00:03 /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data

postgres 33441 33438 0 12:41 ? 00:00:02 postgres: logger process

postgres 33443 33438 0 12:41 ? 00:00:01 postgres: checkpointer process

postgres 33444 33438 0 12:41 ? 00:00:00 postgres: writer process

postgres 33445 33438 0 12:41 ? 00:00:01 postgres: wal writer process

postgres 33446 33438 0 12:41 ? 00:00:00 postgres: autovacuum launcher process

postgres 33447 33438 0 12:41 ? 00:00:01 postgres: stats collector process

postgres 36660 33438 0 12:47 ? 00:00:00 postgres: sj2 devdb 10.220.177.63(57237) idle

root 39915 39837 0 12:53 pts/3 00:00:00 sudo su - postgres

root 39950 39915 0 12:53 pts/3 00:00:00 su - postgres

postgres 39951 39950 0 12:53 pts/3 00:00:00 -bash

postgres 110181 33438 0 15:30 ? 00:00:00 /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data

postgres 110183 11607 0 15:30 pts/2 00:00:00 ps -ef

postgres 110184 11607 0 15:30 pts/2 00:00:00 grep --color=auto postgres

[postgres@SERVER1 data]$

Thanks,

Chiru

Re: Two Postgres master process are showing - one is on and off

From

Adrian Klaver

Date:

20 August 2019, 23:42:34

On 8/20/19 1:32 PM, chiru r wrote:
> Hi All,
> 
> 
> I have observed one of our PostgreSQL DB instance showing two postgres 
> process on Linux server as highlighted. The second postgres process is 
> on and off.

Is the on/off on a regular interval?
My guess is a script(cron possibly) is trying to start the server.

> 
> We did not find any references in logs.

The information:

sudo /etc/init.d/postgresql11 start
Starting PostgreSQL: ok
aklaver@ranger:~> -2019-08-20 13:40:30.097 PDT-0FATAL:  lock file 
"postmaster.pid" already exists
-2019-08-20 13:40:30.097 PDT-0HINT:  Is another postmaster (PID 1694) 
running in data directory "/usr/local/pgsql11/data"?

Is sent to the starting process and does not make it to the server log 
as the server is not started(the 'Starting PostgreSQL' notwithstanding).

> 
> 
> Please provide your advice and help on this issue.
> 
> 
> DB version :  PostgreSQL *9.5.10*
> 
> Server version   :  RHEL *7.6*
> 
> [postgres@PGSERVER data]$ ps -ef|grep postgres
> 
> root       5922 5875  0 Jul31 pts/0    00:00:00 sudo su - postgres
> 
> root       5927 5922  0 Jul31 pts/0    00:00:00 su - postgres
> 
> postgres   5928   5927  0 Jul31 pts/0    00:00:00 -bash
> 
> root      11585  11535  0 11:29 pts/2    00:00:00 sudo su - postgres
> 
> root      11606  11585  0 11:29 pts/2    00:00:00 su - postgres
> 
> postgres  11607  11606  0 11:29 pts/2    00:00:00 -bash
> 
> root      17185  17141  0 Aug19 pts/1    00:00:00 sudo su - postgres
> 
> root      17189  17185  0 Aug19 pts/1    00:00:00 su - postgres
> 
> postgres  17190  17189  0 Aug19 pts/1    00:00:00 -bash
> 
> postgres 33438      1  0 12:41 ?        00:00:03 
> /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data
> 
> postgres  33441  33438  0 12:41 ?        00:00:02 postgres: logger process
> 
> postgres  33443  33438  0 12:41 ?        00:00:01 postgres: checkpointer 
> process
> 
> postgres  33444  33438  0 12:41 ?        00:00:00 postgres: writer process
> 
> postgres  33445  33438  0 12:41 ?        00:00:01 postgres: wal writer 
> process
> 
> postgres  33446  33438  0 12:41 ?        00:00:00 postgres: autovacuum 
> launcher process
> 
> postgres  33447  33438  0 12:41 ?        00:00:01 postgres: stats 
> collector process
> 
> postgres  36660  33438  0 12:47 ?        00:00:00 postgres: sj2 devdb 
> 10.220.177.63(57237) idle
> 
> root      39915  39837  0 12:53 pts/3    00:00:00 sudo su - postgres
> 
> root      39950  39915  0 12:53 pts/3    00:00:00 su - postgres
> 
> postgres  39951  39950  0 12:53 pts/3    00:00:00 -bash
> 
> postgres 110181  33438  0 15:30 ? 00:00:00 
> /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data
> 
> postgres 110183  11607  0 15:30 pts/2    00:00:00 ps -ef
> 
> postgres 110184  11607  0 15:30 pts/2    00:00:00 grep --color=auto postgres
> 
> [postgres@SERVER1 data]$
> 
> Thanks,
> 
> Chiru
> 


-- 
Adrian Klaver
adrian.klaver@aklaver.com

Re: Two Postgres master process are showing - one is on and off

From

chiru r

Date:

21 August 2019, 00:30:44

Thank you Adrian.

Is the on/off on a regular interval?
My guess is a script(cron possibly) is trying to start the server.

Yes, It is regular interval.

No Con-jobs scheduled on server or even remotely.

>
> We did not find any references in logs.

The information:

sudo /etc/init.d/postgresql11 start
Starting PostgreSQL: ok
aklaver@ranger:~> -2019-08-20 13:40:30.097 PDT-0FATAL: lock file
"postmaster.pid" already exists
-2019-08-20 13:40:30.097 PDT-0HINT: Is another postmaster (PID 1694)
running in data directory "/usr/local/pgsql11/data"?

Is sent to the starting process and does not make it to the server log
as the server is not started(the 'Starting PostgreSQL' notwithstanding).

I have verified startup.log and regular postgresql logs also, i did not found above messages.

Thanks,

Chiru

Re: Two Postgres master process are showing - one is on and off

From

Steve Crawford

Date:

21 August 2019, 01:00:56

FWIW, the second process (110181) is a child of the main process (33438). I can't recall if any maintenance process that gets automatically activated (autovacuum, checkpoint, stats, etc.) shows with the same name as the main process.

Cheers,

Steve

On Tue, Aug 20, 2019 at 1:32 PM chiru r <chirupg@gmail.com> wrote:

Hi All,

I have observed one of our PostgreSQL DB instance showing two postgres process on Linux server as highlighted. The second postgres process is on and off.
We did not find any references in logs.

Please provide your advice and help on this issue.

DB version : PostgreSQL 9.5.10
Server version   : RHEL 7.6

[postgres@PGSERVER data]$ ps -ef|grep postgres
root       5922   5875 0 Jul31 pts/0    00:00:00 sudo su - postgres
root       5927   5922 0 Jul31 pts/0    00:00:00 su - postgres
postgres   5928   5927 0 Jul31 pts/0    00:00:00 -bash
root      11585 11535 0 11:29 pts/2    00:00:00 sudo su - postgres
root      11606 11585 0 11:29 pts/2    00:00:00 su - postgres
postgres 11607 11606 0 11:29 pts/2    00:00:00 -bash
root      17185 17141 0 Aug19 pts/1    00:00:00 sudo su - postgres
root      17189 17185 0 Aug19 pts/1    00:00:00 su - postgres
postgres 17190 17189 0 Aug19 pts/1    00:00:00 -bash
postgres 33438      1 0 12:41 ?        00:00:03 /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data
postgres 33441 33438 0 12:41 ?        00:00:02 postgres: logger process
postgres 33443 33438 0 12:41 ?        00:00:01 postgres: checkpointer process
postgres 33444 33438 0 12:41 ?        00:00:00 postgres: writer process
postgres 33445 33438 0 12:41 ?        00:00:01 postgres: wal writer process
postgres 33446 33438 0 12:41 ?        00:00:00 postgres: autovacuum launcher process
postgres 33447 33438 0 12:41 ?        00:00:01 postgres: stats collector process
postgres 36660 33438 0 12:47 ?        00:00:00 postgres: sj2 devdb 10.220.177.63(57237) idle
root      39915 39837 0 12:53 pts/3    00:00:00 sudo su - postgres
root      39950 39915 0 12:53 pts/3    00:00:00 su - postgres
postgres 39951 39950 0 12:53 pts/3    00:00:00 -bash
postgres 110181 33438 0 15:30 ?        00:00:00 /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data
postgres 110183 11607 0 15:30 pts/2    00:00:00 ps -ef
postgres 110184 11607 0 15:30 pts/2    00:00:00 grep --color=auto postgres
[postgres@SERVER1 data]$

Thanks,
Chiru

Re: Two Postgres master process are showing - one is on and off

From

Steve Crawford

Date:

21 August 2019, 01:01:47

(sorry for the top-post - blame GMail)

-Steve

Sv: Two Postgres master process are showing - one is on and off

From

Andreas Joseph Krogh

Date:

21 August 2019, 01:39:46

På tirsdag 20. august 2019 kl. 22:32:25, skrev chiru r <chirupg@gmail.com>:

Hi All,

I have observed one of our PostgreSQL DB instance showing two postgres process on Linux server as highlighted. The second postgres process is on and off.
We did not find any references in logs.
[...]
postgres 33438 1 0 12:41 ? 00:00:03 /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data

[...]

postgres 110181 33438 0 15:30 ? 00:00:00 /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data

Strange, the second is a child of the first...

--
Andreas Joseph Krogh

Re: Two Postgres master process are showing - one is on and off

From

Laurenz Albe

Date:

21 August 2019, 10:34:43

chiru r wrote:
> I have observed one of our PostgreSQL DB instance showing two postgres process on Linux server as highlighted. The
secondpostgres process is on and off.
 
> We did not find any references in logs.
> 
> Please provide your advice and help on this issue.
> 
> DB version :  PostgreSQL  9.5.10
> Server version   :  RHEL 7.6
>  
> [postgres@PGSERVER data]$ ps -ef|grep postgres
> postgres  33438      1  0 12:41 ?        00:00:03 /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data
> [...]
> postgres 110181  33438  0 15:30 ?        00:00:00 /u01/postgres/9.5/bin/postgres -D /u02/pgdata01/9.5/data

Perhaps it is a new client connection, and the process title just hasn't been changed (yet).

What is your setting for "update_process_title"?

Yours,
Laurenz Albe
-- 
Cybertec | https://www.cybertec-postgresql.com