Re: 64-bit CommandIds

[Hans-Juergen Schoenig <hs(at)cybertec(dot)at>]

Tom Lane wrote:
> Hans-Juergen Schoenig <hs(at)cybertec(dot)at> writes:
>   
> > Alvaro Herrera wrote:
> >     
> > > Question for Hans-Juergen and Zoltan: have you tested 8.3 and do you
> > > still see the need for this?
> > >       
>
>   
> > i have seen this problem two or three times within the past 2-3 years or 
> > so. so, it can basically happen in the field for some special purpose 
> > applications but i don't see this as an every day problem. it would be 
> > nice to have it in.
> >     
>
> So these experiences were pre-8.3, right?
>
> The reason that I'm harping on that is that plpgsql does a
> CommandCounterIncrement for each expression it evaluates, whether
> or not there's any visible database access.  As of 8.3 that won't
> cause consumption of CIDs, but before it did.  I suspect that in a
> lot of real-world scenarios, CID consumption from triggers will be
> down by an order of magnitude.
>
> 			regards, tom lane
>   


we found those problems when we dealt with stored procedures basically 
(during huge analysis and data modification transactions - rollup and 
materialize stuff, basically). i would think as well that it should have 
improved a lot.

i have not tested with 8.3, however.
on 8.2 it took something like 18 hours to reach that threshold - just to 
give you an impression.

   many thanks,

      hans



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