Re: Possible interesting extra information for explain analyze? - Mailing list pgsql-performance

From Tom Lane
Subject Re: Possible interesting extra information for explain analyze?
Date
Msg-id 5599.1109347510@sss.pgh.pa.us
Whole thread Raw
In response to Possible interesting extra information for explain analyze?  (Jeff <threshar@torgo.978.org>)
List pgsql-performance
Jeff <threshar@torgo.978.org> writes:
> Given some recent posts / irc issues with dead tuple bloat..
> And given that a lot of these people have at least been smart enough to
> explain analyze would it be A. possible B. useful C. None of the above
> to have various "scan" nodes of explain analyze also report how many
> invisible / dead tuples they had to disqualify (Just to clarify, they
> matched the search criteria, but were invisible due to MVCC rules).

I think this would not help a whole lot because (particularly on
indexscans) you won't get a very accurate picture of the true extent
of bloat.  The contrib/pgstattuple utility is more useful for measuring
that sort of thing.

            regards, tom lane

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