Thread: WARNING : pgstat wait timeout - Postgres 9.1

WARNING : pgstat wait timeout - Postgres 9.1

From

Mathieu Guerin

Date:

23 May 2013, 15:32:19

Hello,

I am facing a problem with pgstat as my subject says. I known, some topics are open about that, but I would like to go deeper.

Some person told that the better way to don't have this message anymore is to configure pgstat.stat to be loaded in the RAM with a tmpfs mount point.

What are the consequences ? Because this file will be remove if the server reboot.

If we change the parameter stats_temp_directory is it necessary to reboot the server ?

When I lauch a SHOW ALL; command, the parameter stats_temp_director is not here.

For information, my pgstat.stat file is up to 1,3MB.

Thank you for your help.

Math

Re: WARNING : pgstat wait timeout - Postgres 9.1

From

Michael Paquier

Date:

24 May 2013, 01:55:31

On Thu, May 23, 2013 at 9:31 PM, Mathieu Guerin <mathieu.guerin64@gmail.com> wrote:

What are the consequences ? Because this file will be remove if the server reboot.

Those temporary statistics are stored in global directory when server shuts down, so the risk here would be to lose a portion of this data in the case of a crash, either at PG or at OS level.

If we change the parameter stats_temp_directory is it necessary to reboot the server ?

No, sending SIGHUP to the server is enough.

When I lauch a SHOW ALL; command, the parameter stats_temp_director is not here.

You should get it...
stats_temp_directory | pg_stat_tmp | Writes temporary statistics files to the specified directory.

--
Michael

Re: WARNING : pgstat wait timeout - Postgres 9.1

From

Mathieu Guerin

Date:

24 May 2013, 13:13:44

Hello,

Thanks a lot for your answers.

> You should get it...
> stats_temp_directory | pg_stat_tmp | Writes temporary statistics files to the specified directory.

I don't know why i don't get it. I am in 9.1 version...

Moreover, when I mount pg_stat_tmp in a tmpfs, the warning messages decrease the warning messages decrease from 1 each minutes to 1 each five secondes. I don't have any others logs warning but the file pg_stat.stat in the mounting point is not created... I tryed before on a test environment and it works...

If you have any ideas...

Thanks a lot.

Regards,
Math

2013/5/24 Michael Paquier <michael.paquier@gmail.com>

On Thu, May 23, 2013 at 9:31 PM, Mathieu Guerin <mathieu.guerin64@gmail.com> wrote:
What are the consequences ? Because this file will be remove if the server reboot.
Those temporary statistics are stored in global directory when server shuts down, so the risk here would be to lose a portion of this data in the case of a crash, either at PG or at OS level.

If we change the parameter stats_temp_directory is it necessary to reboot the server ?
No, sending SIGHUP to the server is enough.

When I lauch a SHOW ALL; command, the parameter stats_temp_director is not here.
You should get it...
stats_temp_directory | pg_stat_tmp | Writes temporary statistics files to the specified directory.

--
Michael

Re: WARNING : pgstat wait timeout - Postgres 9.1

From

Mathieu Guerin

Date:

24 May 2013, 14:49:31

About the stats_temp_directory, I didn't run as root...

Now I'm sure the configurations are correct.

I think, I have too much IO to use stats. I will ever have this message...

Maybe I can disable this option.

Do you know what it really impact ?

Thanks.

Math

2013/5/24 Mathieu Guerin <mathieu.guerin64@gmail.com>

Hello,

Thanks a lot for your answers.

> You should get it...
> stats_temp_directory | pg_stat_tmp | Writes temporary statistics files to the specified directory.

I don't know why i don't get it. I am in 9.1 version...

Moreover, when I mount pg_stat_tmp in a tmpfs, the warning messages decrease the warning messages decrease from 1 each minutes to 1 each five secondes. I don't have any others logs warning but the file pg_stat.stat in the mounting point is not created... I tryed before on a test environment and it works...

If you have any ideas...
Thanks a lot.
Regards,
Math

2013/5/24 Michael Paquier <michael.paquier@gmail.com>

On Thu, May 23, 2013 at 9:31 PM, Mathieu Guerin <mathieu.guerin64@gmail.com> wrote:
What are the consequences ? Because this file will be remove if the server reboot.
Those temporary statistics are stored in global directory when server shuts down, so the risk here would be to lose a portion of this data in the case of a crash, either at PG or at OS level.

If we change the parameter stats_temp_directory is it necessary to reboot the server ?
No, sending SIGHUP to the server is enough.

When I lauch a SHOW ALL; command, the parameter stats_temp_director is not here.
You should get it...
stats_temp_directory | pg_stat_tmp | Writes temporary statistics files to the specified directory.

--
Michael