Re: FILLFACTOR and increasing index - Mailing list pgsql-general

From Leonardo Francalanci
Subject Re: FILLFACTOR and increasing index
Date
Msg-id 105116.24690.qm@web29006.mail.ird.yahoo.com
Whole thread Raw
In response to Re: FILLFACTOR and increasing index  (Simon Riggs <simon@2ndQuadrant.com>)
Responses Re: FILLFACTOR and increasing index
Re: FILLFACTOR and increasing index
List pgsql-general
> It will be really useful to see some test  results where you alter the
> fillfactor and report various  measurables.


It's not that easy... stressing "only" the index insertion
speed won't be simple. I would have liked some "theory"...
The docs seem to imply there are some guidelines, it's
just that it's too cryptic:

"for heavily updated tables a smaller fillfactor is better
to minimize the need for page splits"


  "heavily updated" -> does it mean tables that are inserted/updated
or only "updated"???

"leaf pages are filled to this percentage [...] when extending the index
at the right (adding new largest key values)."


Does it mean that since I will (almost) always add new largest key
values, I should have a big or small FILLFACTOR???


I know that theory is one thing and real testing another; but I can't
test everything; if there are some (proved?) guidelines I'd like to
use them (example: I'm not going to test that fillfactor in table creation
in my case won't make any difference in   performance; I trust the
docs and the fact that "it makes sense").


pgsql-general by date:

Previous
From: Guillaume Lelarge
Date:
Subject: Re: simple update query too long
Next
From: tv@fuzzy.cz
Date:
Subject: Re: simple update query too long