Обсуждение: Re: [HACKERS] suspected problem with cache updates

> >
> > I've noticed recently that after making certain changes to the
> > database (adding indices, attributes) they aren't immediately known
> > about.  for example, I add an attribute, then try to update that
> > attribute it tells me it doesn't exist.  if I exist psql and start a
> > new connection all is well.  but it doesn't happen consistently..
> >
> >
>
>     Looks like problems in the syscache/catcache invalidation
>     routines.
>

This existed in an older version, but I could almost swear that someone
fixed it.

Bruce, do you have old versions of the TODO lists around to check on
this one?  I specifically remember the part about adding an attribute
and it not being there until the next session.

darrenk

Darren wrote:
>
> > >
> > > I've noticed recently that after making certain changes to the
> > > database (adding indices, attributes) they aren't immediately known
> > > about.  for example, I add an attribute, then try to update that
> > > attribute it tells me it doesn't exist.  if I exist psql and start a
> > > new connection all is well.  but it doesn't happen consistently..
> > >
> > >
> >
> >     Looks like problems in the syscache/catcache invalidation
> >     routines.
> >
>
> This existed in an older version, but I could almost swear that someone
> fixed it.

    I  fixed  something  there  lately when it came to pg_shadow,
    where the required update  on  pg_class  during  revoke/grant
    just  outdated  the  syscache  tuple  for  pg_shadow, but the
    permission checking code needed that.

    But this problem looks  different.  This  time  the  pg_class
    tuple  for a user table is updated where that table had to be
    flushed from the relcache and reopened. Cannot reproduce  the
    error  here.   If  I  alter  table  add  field,  they show up
    immediately in the same session.

>
> Bruce, do you have old versions of the TODO lists around to check on
> this one?  I specifically remember the part about adding an attribute
> and it not being there until the next session.
>
> darrenk
>
>


Jan

--

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me.                                  #
#======================================== jwieck@debis.com (Jan Wieck) #

>
> This existed in an older version, but I could almost swear that someone
> fixed it.
>
> Bruce, do you have old versions of the TODO lists around to check on
> this one?  I specifically remember the part about adding an attribute
> and it not being there until the next session.
>

I think that was a very old bug.  It involved ALTER TABLE ADD and the
thing not appearing until the next session, I think.  It has to do with
the attribute cache.  The only old TODO versions I have are in the old
releases.

--
Bruce Momjian                          |  830 Blythe Avenue
maillist@candle.pha.pa.us              |  Drexel Hill, Pennsylvania 19026
  +  If your life is a hard drive,     |  (610) 353-9879(w)
  +  Christ can be your backup.        |  (610) 853-3000(h)

It must be reappearing again.  It happened under 6.3

On Fri, 13 March 1998, at 17:20:52, Bruce Momjian wrote:

> I think that was a very old bug.  It involved ALTER TABLE ADD and the
> thing not appearing until the next session, I think.  It has to do with
> the attribute cache.  The only old TODO versions I have are in the old
> releases.
>
> --
> Bruce Momjian                          |  830 Blythe Avenue
> maillist@candle.pha.pa.us              |  Drexel Hill, Pennsylvania 19026
>   +  If your life is a hard drive,     |  (610) 353-9879(w)
>   +  Christ can be your backup.        |  (610) 853-3000(h)

It certainly didn't happen very consistently, in fact, only once.

On Fri, 13 March 1998, at 19:43:48, Jan Wieck wrote:

>     But this problem looks  different.  This  time  the  pg_class
>     tuple  for a user table is updated where that table had to be
>     flushed from the relcache and reopened. Cannot reproduce  the
>     error  here.   If  I  alter  table  add  field,  they show up
>     immediately in the same session.
>
> >
> > Bruce, do you have old versions of the TODO lists around to check on
> > this one?  I specifically remember the part about adding an attribute
> > and it not being there until the next session.
> >
> > darrenk
> >
> >
>
>
> Jan