Thread: external_pid_file not removed on postmaster exit

external_pid_file not removed on postmaster exit

From
Peter Eisentraut
Date:
It seems strange that the external_pid_file is never removed.  There is
even a C comment about it:

/* Should we remove the pid file on postmaster exit? */

I think it should be removed with proc_exit hook just like the main
postmaster.pid file.

Does anyone remember why this was not done originally or have any
concerns?




Re: external_pid_file not removed on postmaster exit

From
Amit kapila
Date:
>From: pgsql-hackers-owner@postgresql.org [pgsql-hackers-owner@postgresql.org] on behalf of Peter Eisentraut
[peter_e@gmx.net]
> Sent: Friday, July 27, 2012 10:39 AM

> It seems strange that the external_pid_file is never removed.  There is
> even a C comment about it:

> /* Should we remove the pid file on postmaster exit? */

> I think it should be removed with proc_exit hook just like the main
> postmaster.pid file.

external_pid_file is created first time when it is enabled in postgresql.conf
I think it should be removed once the parameter external_pid_file is unset;

Making handling of both postmaster.pid and external_pid_file same in terms of creation and removal may not be best
choice
as both have different purpose.



With Regards,
Amit Kapila.

Re: external_pid_file not removed on postmaster exit

From
Tom Lane
Date:
Amit kapila <amit.kapila@huawei.com> writes:
>> I think it should be removed with proc_exit hook just like the main
>> postmaster.pid file.

> external_pid_file is created first time when it is enabled in postgresql.conf
> I think it should be removed once the parameter external_pid_file is unset; 

Unset?  If that parameter is not PGC_POSTMASTER, it certainly ought to
be.  In any case, that has little to do with what Peter is complaining
about ...
        regards, tom lane


Re: external_pid_file not removed on postmaster exit

From
Amit kapila
Date:
> From: Tom Lane [tgl@sss.pgh.pa.us]
> Sent: Saturday, July 28, 2012 9:46 PM
Amit kapila <amit.kapila@huawei.com> writes:
>>> I think it should be removed with proc_exit hook just like the main
>>> postmaster.pid file.

>> external_pid_file is created first time when it is enabled in postgresql.conf
>> I think it should be removed once the parameter external_pid_file is unset;

> Unset?
By Unset, I mean to say when the configuration parameter 'external_pid_file' is disabled (#external_pid_file).
But if the path/filename is changed to different name across restart of server, it will not be able to delete the
previousfile.  
So it will not workout the way I was trying to think.

However if it is deleted at proc_exit as suggested by Peter, there will be no problem.

The reason why I have thought the file not to get deleted at every proc_exit, is
a. Initially I thought it might be un-necessary to delete and re-create the file at server shutdown and start.
b. I was not sure if this file has usage only till server is running.


With Regards,
Amit Kapila.



Re: external_pid_file not removed on postmaster exit

From
Peter Eisentraut
Date:
On Fri, 2012-07-27 at 08:09 +0300, Peter Eisentraut wrote:
> It seems strange that the external_pid_file is never removed.  There is
> even a C comment about it:
>
> /* Should we remove the pid file on postmaster exit? */
>
> I think it should be removed with proc_exit hook just like the main
> postmaster.pid file.
>
> Does anyone remember why this was not done originally or have any
> concerns?

Since that was not the case, I propose the attached patch to unlink the
external pid file.

Attachment