From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jeff Janes <jeff.janes@gmail.com>
cc: Thomas Kellerer <spam_eater@gmx.net>,
        pgsql-performance@lists.postgresql.org
Subject: Re: Bloom index cost model seems to be wrong
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Comments: In-reply-to Jeff Janes <jeff.janes@gmail.com>
	message dated "Tue, 12 Feb 2019 14:56:40 -0500"
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Date: Tue, 12 Feb 2019 16:17:23 -0500
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Jeff Janes <jeff.janes@gmail.com> writes:
> In order for bloom (or any other users of CREATE ACCESS METHOD, if there
> are any) to have a fighting chance to do better, I think many of selfuncs.c
> currently private functions would have to be declared in some header file,
> perhaps utils/selfuncs.h.  But that then requires a cascade of other
> inclusions.  Perhaps that is why it was not done.

I'm just in the midst of refactoring that stuff, so if you have
suggestions, let's hear 'em.

It's possible that a good cost model for bloom is so far outside
genericcostestimate's ideas that trying to use it is not a good
idea anyway.

			regards, tom lane