Re: HOT patch - version 15 - Mailing list pgsql-patches

From Tom Lane
Subject Re: HOT patch - version 15
Date
Msg-id 26448.1189030536@sss.pgh.pa.us
Whole thread Raw
In response to Re: HOT patch - version 15  (Bruce Momjian <bruce@momjian.us>)
Responses Re: HOT patch - version 15  (Gregory Stark <stark@enterprisedb.com>)
Re: HOT patch - version 15  (Simon Riggs <simon@2ndquadrant.com>)
List pgsql-patches
Bruce Momjian <bruce@momjian.us> writes:
> Tom Lane wrote:
>> Uh, why would any of this code at all execute during a pure lookup?

> No idea.  It seems an index lookup tries to prune a heap chain, and he
> was asking if it should look at other chains on the page;  I said not.
> Whether the index lookup should prune the heap chain is another issue.

ISTM the only time we should be doing HOT cleanup work is when we are
trying to insert a new tuple on that page --- and maybe even only when
we try and it doesn't fit straight off.  Otherwise you're pushing
maintenance work into foreground query pathways, which is exactly where
I don't think we should be headed.

            regards, tom lane

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