Re: Modifying TOAST thresholds - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: Modifying TOAST thresholds
Date
Msg-id 200704270037.l3R0bnx13336@momjian.us
Whole thread Raw
In response to Re: Modifying TOAST thresholds  (Gregory Stark <stark@enterprisedb.com>)
List pgsql-hackers
I have seen no one do peroformance testing of this, so it seems it will
have to wait for 8.4.

---------------------------------------------------------------------------

Gregory Stark wrote:
> "Tom Lane" <tgl@sss.pgh.pa.us> writes:
> 
> > What I would definitely like to see for 8.3 is some performance testing
> > done to determine whether we ought to change the current defaults.
> > (Both TOAST_TUPLES_PER_PAGE and EXTERN_TUPLES_PER_PAGE ought to be looked
> > at.)
> 
> It will take some thinking before it's even clear what we should be measuring.
> The "optimal" value will depend heavily on the usage pattern so the best value
> for the default will be something hand-wavy like "the smallest tuple size
> where the cost of a select including the column is greater than the time saved
> on a select not including the column" or something like that.
> 
> -- 
>   Gregory Stark
>   EnterpriseDB          http://www.enterprisedb.com
> 
> 
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--  Bruce Momjian  <bruce@momjian.us>          http://momjian.us EnterpriseDB
http://www.enterprisedb.com
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