From: "Molitor, Stephen L" <Stephen.L.Molitor@...>
Date: 2005-03-06T13:02:07+09:00
Subject: Re: plruby bug with postgres 8.0 composite types / ref count leak -	 FIX?

------_=_NextPart_001_01C52201.39BC1D0F
Content-Type: text/plain;
	charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

I *might* have a fix.  Changing plruby.c lines 892 - 898 from this:

            if (typeStruct->typrelid !=3D InvalidOid) {
                prodesc->arg_is_rel[i] =3D 1;
                ReleaseSysCache(typeTup);
            }
            else {
                prodesc->arg_is_rel[i] =3D 0;
            }=20

to simply this:

                prodesc->arg_is_rel[i] =3D 0;

makes the problem go away.   (In other words, removing the !=3D =
InvalidOid check.) =20

It seems that the problem isn't a catcache reference leak, but rather =
releasing the same thing more than once.  Of course, my 'fix' might just =
be introducing a leak in other circumstances, although it does seem to =
avoid the double release in my test case.  I just started peaking at the =
plruby c code today; haven't really grokked it yet.  Anyway, maybe this =
will help.

To Guy Decoux (plruby author) -- thanks for a pretty slick module.  I =
just started playing with it, but this issue aside, it seems to =
integrate pretty darn well with postgresql.   Ruby and postgresql seem =
like a good fit.

Steve

-----Original Message-----
From: Molitor, Stephen L
Sent: Sat 3/5/2005 9:13 PM
To: ruby-talk ML
Subject: Re: plruby bug with postgres 8.0 composite types / ref count =
leak?
=20
Sorry, minor typo.  I copied and pasted from my psql session and forgot =
to remove all the prompts.  Without the prompts, running the following =
(you can feed it in to psql from the command line) causes the error:

create type t as ( name text );
create function f(t) returns integer as '42' language 'plruby';
select f(ROW('a name'));


Steve


-----Original Message-----
From: Molitor, Stephen L
Sent: Sat 3/5/2005 9:08 PM
To: ruby-talk ML
Subject: plruby bug with postgres 8.0 composite types / ref count leak?
=20
I tried using the new postgres composite types features as described in =
the new manual.

With the following versions:

plruby 0.4.3
postgresql 8.0.1
ruby 1.8.2
Mac OS X 10.3.8 (panther)

when I run the following in psql:

create type t as ( name text );
test=3D# create function f(t) returns integer as '42' language 'plruby';
select f(ROW('a name'));

I get the following error:
ERROR:  catcache reference 0x430388 is not owned by resource owner =
Portal

However, if I use pl/sql, running this works fine:

create function f2(t) returns integer as 'select 42' language sql;
select f2(ROW('a name'));

I get 42 back. =20

The error appears to be thrown on line 609 in the function =
ResourceOwnerForgetCatCacheRef in resowner.c in the postgres 8.0.1 =
sources.  The only place that this method seems to get called is on line =
1293 in the function ReleaseCatCache in catcache.c.  This is called =
immediately after it decrements the ref count on the catcache.   So =
maybe there's some sort of reference count leak or something.

I have trouble reproducing it, but using the old syntax with postgres =
7.4.7 I would sometimes get warnings about a catcache leak, the error =
saying something about 'catcache ref count has reached -1'.   So I'm =
guessing the leak has always existing but fails hard with 8.0.

Anyway, any help would be appreciated!

Steve


------_=_NextPart_001_01C52201.39BC1D0F--