R: BUG #6342: libpq blocks forever in "poll" function

The client program and the postgres server are on the same host, client con=
nects to 127.0.0.1.
In the meantime, my original program blocks (not my example but very probab=
ly the reasons are the same).=20

I typed "ps -C testprogramname -o wchan:80=3D" and the output was only a si=
ngle dash ( "-" ).
I searched for the complete stack in /proc/$pid/stack (where $pid) was the =
pid of my process but this file doesn't exists !! Why ?=20

I'm waiting for my example to block in order to send you what you request m=
e about the test program (even if the output almost surely will be the same=
).

Regards,=20
Andrea Grassi

-----Messaggio originale-----
Da: Craig Ringer [mailto:ringerc@ringerc.id.au]=20
Inviato: venerd=C3=AC 16 dicembre 2011 9.24
A: andreagrassi@sogeasoft.com
Cc: pgsql-bugs@postgresql.org
Oggetto: Re: [BUGS] BUG #6342: libpq blocks forever in "poll" function

On 12/16/2011 03:45 PM, andreagrassi@sogeasoft.com wrote:
> The following bug has been logged on the website:
>
> Bug reference:      6342
> Logged by:          Andrea Grassi
> Email address:      andreagrassi@sogeasoft.com
> PostgreSQL version: 8.4.8
> Operating system:   SUSE SLES 10 SP4 64 BIT
> Description:
>
> Hi,
> I have a big and strange problem. Sometimes, libpq remains blocked in =E2=
=80=9Cpoll=E2=80=9D
> function even if the server has already answered to the query. If I attach
> to the process using kdbg I found this stack:
>
> __kernel_vsyscall()
> poll()                          from /lib/libc.so.6
Given all you described (thanks for all the detail!) then if client and=20
server are on different hosts this could easily be a NIC driver or HW=20
issue. It'd be interesting to see the output of:

ps -C testprogramname -o wchan:80=3D

--
Craig Ringer