debugger question

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On Mon, Apr 12, 2010 at 08:31:38PM -0700, Murali M. Krishna wrote:

Hello:

I am brand new to Postgresql.

I ran the following commands.
./configure
gmake
su
gmake install
adduser postgres
mkdir /usr/local/pgsql/data
chown postgres /usr/local/pgsql/data
su - postgres
/usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data
/usr/local/pgsql/bin/postmaster -D /usr/local/pgsql/data >logfile 2>&1 &
/usr/local/pgsql/bin/createdb test
/usr/local/pgsql/bin/psql test

I would like to start using gdb.

What is the simplest way of doing this? I read the instructions
on this page

http://sites.google.com/a/cs.berkeley.edu/cs186-fa09/home/assignments/assignment2/pggdb

, but this is what I get.

gdb) attach 1731
Attaching to program: /usr/local/pgsql/bin/postgres, process 1731
ptrace: Operation not permitted.
(gdb) break cost_seqscan
Breakpoint 1 at 0x81cdf97: file costsize.c, line 163.
(gdb) c
The program is not being run.

Hm. Seems you got the right PID (gdb finds the executable after all).
Are you perhaps running under SELinux? (i just boldly assumed some
GNU/Linux). Which distribution, which kernel version (there seems to be
a bug in 2.4-ish Linux kernels which manifests itself like that, but
that's quite a while ago).

Next time, please tell us what OS is under you (although it might be fun
to watch people make wild guesses :)

Regards
- -- tomás
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The OS is

Fedora 12.

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--- On Mon, 4/12/10, tomas@tuxteam.de <tomas@tuxteam.de> wrote:

From: tomas@tuxteam.de <tomas@tuxteam.de>
Subject: Re: [HACKERS] debugger question
To: "Murali M. Krishna" <murali1729@yahoo.com>
Cc: pgsql-hackers@postgresql.org
Date: Monday, April 12, 2010, 9:28 PM

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Hash: SHA1

On Mon, Apr 12, 2010 at 08:31:38PM -0700, Murali M. Krishna wrote:

Hello:

I am brand new to Postgresql.

I ran the following commands.
./configure
gmake
su
gmake install
adduser postgres
mkdir /usr/local/pgsql/data
chown postgres /usr/local/pgsql/data
su - postgres
/usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data
/usr/local/pgsql/bin/postmaster -D /usr/local/pgsql/data >logfile 2>&1 &
/usr/local/pgsql/bin/createdb test
/usr/local/pgsql/bin/psql test

I would like to start using gdb.

What is the simplest way of doing this? I read the instructions
on this page

http://sites.google.com/a/cs.berkeley.edu/cs186-fa09/home/assignments/assignment2/pggdb

, but this is what I get.

gdb) attach 1731
Attaching to program: /usr/local/pgsql/bin/postgres, process 1731
ptrace: Operation not permitted.
(gdb) break cost_seqscan
Breakpoint 1 at 0x81cdf97: file costsize.c, line 163.
(gdb) c
The program is not being run.

Hm. Seems you got the right PID (gdb finds the executable after all).
Are you perhaps running under SELinux? (i just boldly assumed some
GNU/Linux). Which distribution, which kernel version (there seems to be
a bug in 2.4-ish Linux kernels which manifests itself like that, but
that's quite a while ago).

Next time, please tell us what OS is under you (although it might be fun
to watch people make wild guesses :)

Regards
- -- tomás
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"Murali M. Krishna" <murali1729@yahoo.com> writes:

I would like to start using gdb.
...
, but this is what I get.

gdb) attach 1731
Attaching to program: /usr/local/pgsql/bin/postgres, process 1731
ptrace: Operation not permitted.

Try running gdb as the postgres user, ie, su to postgres first.
If that doesn't work, see if it works after disabling selinux
(and if so, file a bug, because selinux shouldn't prevent it).

regards, tom lane