Horton

Re: Should heapam_estimate_rel_size consider fillfactor?

Heikki Linnakangas <hlinnaka@iki.fi>

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From: Heikki Linnakangas <hlinnaka@iki.fi>
To: Tomas Vondra <tomas@vondra.me>, Peter Eisentraut <peter@eisentraut.org>, Corey Huinker <corey.huinker@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2025-02-18T12:29:48Z
Lists: pgsql-hackers 
On 18/02/2025 14:01, Tomas Vondra wrote:
> On 2/4/25 17:54, Tomas Vondra wrote:
>> On 2/4/25 16:02, Tomas Vondra wrote:
>>> ...
>>>
>>> Thanks for the report. And yeah, clamping it to 1 seems like the right
>>> fix for this. I wonder if it's worth inventing some sort of test for
>>> this, shouldn't be too hard I guess.
>>>
>>> In any case, I'll take care of the fix/backpatch soon.
>>
>> Here's a proposed fix, including a simple test in the stats suite.
> 
> Here's a slightly improved fix, with a proper commit message and
> simplified test case. I plan to push this once the releases get out (I
> know it was stamped already, but ...).

Looks good, thanks!

-- 
Heikki Linnakangas
Neon (https://neon.tech)

Commits

  1. Correct relation size estimate with low fillfactor

  2. Consider fillfactor when estimating relation size