Re: [HACKERS] Priorities for 6.6

From: wieck(at)debis(dot)com (Jan Wieck)
To: hannu(at)trust(dot)ee (Hannu Krosing)
Cc: tgl(at)sss(dot)pgh(dot)pa(dot)us, dhogaza(at)pacifier(dot)com, pgsql-hackers(at)postgreSQL(dot)org
Subject: Re: [HACKERS] Priorities for 6.6
Date: 1999-06-06 18:47:03
Message-ID: m10qhwl-0003kGC@orion.SAPserv.Hamburg.dsh.de
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

>
> Tom Lane wrote:
> >
> > Don Baccus <dhogaza(at)pacifier(dot)com> writes:
> > > While I don't doubt your analysis is correct for the case you've
> > > uncovered, it doesn't explain why surrounding a bunch of selects
> > > with a begin/end block greatly descreases disk activity for tables
> > > that don't change.
> >
> > Hmm, I'm not sure why that should be, either. Anyone?
>
> >From a recent discussion I remember that every block that is read
> in is marked as dirty, regardless of weather it is modified or not.
>
> It is not a genuine bug (as it only slows thong down instead of
> getting wrong results), but still a misfeature.
>
> It is most likely an ancient quickfix for some execution path that
> failed to set the dirty mark when it should have.

Can't believe that this is true - uhhhhhh!

If it is, then it's surely a severe BUG!

Jan

--

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

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Oleg Bartunov 1999-06-06 18:58:22 Re: [HACKERS] Priorities for 6.6
Previous Message Jan Wieck 1999-06-06 18:44:49 Re: [HACKERS] Priorities for 6.6