Re: WARNING : pgstat wait timeout - Postgres 9.1

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

On Thu, May 23, 2013 at 9:31 PM, Mathieu Guerin
<mathieu(dot)guerin64(at)gmail(dot)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

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(dot)paquier(at)gmail(dot)com>

>
>
>
> On Thu, May 23, 2013 at 9:31 PM, Mathieu Guerin <
> mathieu(dot)guerin64(at)gmail(dot)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
>

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(dot)guerin64(at)gmail(dot)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(dot)paquier(at)gmail(dot)com>
>
>>
>>
>>
>> On Thu, May 23, 2013 at 9:31 PM, Mathieu Guerin <
>> mathieu(dot)guerin64(at)gmail(dot)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
>>
>
>