Thread: BUG #7631: tcp_keepalives_* parameters ignored in postgresql.conf - related to 9.0.10 or 9.0.9 patch?

The following bug has been logged on the website:

Bug reference:      7631
Logged by:          Rob Johnson
Email address:      robj@hightouchinc.com
PostgreSQL version: 9.0.10
Operating system:   RHEL 5.8
Description:        =


The last four lines in my postgresql.conf file, under
/var/lib/pgsql/9.0/data, are:

# (15 per hour * 6 hours =3D 90)
tcp_keepalives_count=3D90
tcp_keepalives_idle=3D240
tcp_keepalives_interval=3D240

I last changed this file on August 13th, 2012.  I remember that when I added
these parameters to postgresql.conf, they showed the correct values when I
ran "show all" at the psql command line.  However, they now all display 0
values.

I ran "show all" and included some of the output below.  The config_file
parameter shows that when the instance started, it used the postgresql.conf
file that includes my tcp_keepalives_* parameters.  The "max_connections"
parameter is 600, which I also have defined in that postgresql.conf file, so
I know that at least *some* non-default parameter values are processed
properly.

I *suspect* this problem was created by the 9.0.10 or 9.0.9 patch, because I
was running 9.0.8 when I changed the tcp_keepalives_* parameters, but that's
just an uninformed guess.

(I updated my postgresql* packages from the PGDG repository to 9.0.9 on
August 20th, and to 9.0.10 on September 25th.)

postgres=3D# show all;
              name               |                 setting                 |
                                                         description

---------------------------------+-----------------------------------------=
+--------------------------------------------------------------------------=
-------
----------------------------------------------
...
 config_file                     | /var/lib/pgsql/9.0/data/postgresql.conf |
Sets the server's main configuration file.
...
 max_connections                 | 600                                     |
Sets the maximum number of concurrent connections.
...
 tcp_keepalives_count            | 0                                       |
Maximum number of TCP keepalive retransmits.
 tcp_keepalives_idle             | 0                                       |
Time between issuing TCP keepalives.
 tcp_keepalives_interval         | 0                                       |
Time between TCP keepalive retransmits.
...
(208 rows)

robj@hightouchinc.com writes:
> The last four lines in my postgresql.conf file, under
> /var/lib/pgsql/9.0/data, are:

> # (15 per hour * 6 hours = 90)
> tcp_keepalives_count=90
> tcp_keepalives_idle=240
> tcp_keepalives_interval=240

> I last changed this file on August 13th, 2012.  I remember that when I added
> these parameters to postgresql.conf, they showed the correct values when I
> ran "show all" at the psql command line.  However, they now all display 0
> values.

I believe those will read as zero in a session connected over a Unix
socket.  Try it in a session connected over TCP ...

            regards, tom lane

Rob Johnson <robj@hightouchinc.com> writes:
>> I believe those will read as zero in a session connected over a Unix
>> socket.  Try it in a session connected over TCP ...

> You are correct.  In a TCP session, I see the values that were set in postgresql.conf.

OK.  It doesn't look like this behavior is actually documented.  I'll
go fix that.

            regards, tom lane

>=20
> robj@hightouchinc.com writes:
> > The last four lines in my postgresql.conf file, under
> > /var/lib/pgsql/9.0/data, are:
>=20
> > # (15 per hour * 6 hours =3D 90)
> > tcp_keepalives_count=3D90
> > tcp_keepalives_idle=3D240
> > tcp_keepalives_interval=3D240
>=20
> > I last changed this file on August 13th, 2012.  I remember that when
> I added
> > these parameters to postgresql.conf, they showed the correct values
> when I
> > ran "show all" at the psql command line.  However, they now all
> display 0
> > values.
>=20
> I believe those will read as zero in a session connected over a Unix
> socket.  Try it in a session connected over TCP ...
>=20
>             regards, tom lane

You are correct.  In a TCP session, I see the values that were set in postg=
resql.conf.
Thank you for the quick answer.

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