From: | Kenneth Marshall <ktm(at)it(dot)is(dot)rice(dot)edu> |
---|---|
To: | Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> |
Cc: | Simon Riggs <simon(at)2ndquadrant(dot)com>, pgsql-hackers(at)postgresql(dot)org |
Subject: | Re: Minor TODO list changes |
Date: | 2004-11-04 17:05:41 |
Message-ID: | 20041104170541.GB18703@it.is.rice.edu |
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Lists: | pgsql-hackers |
Bruce,
Just to chime in. I also agree that fillfactor is useful. I have
been investigating different index variants and different fill
factors can greatly influence the performance of the index. I
also think it may play a key role in minimizing the small table/
many inserts/updates performance problem.
--Ken
On Thu, Nov 04, 2004 at 11:51:15AM -0500, Bruce Momjian wrote:
>
> OK, I updated all your items. I removed fillfactor because I thought I
> was the only one who thought it was valuable and as I remember it was
> mostly useful for ISAM, which we don't support. Can you think of a use
> for a non-100% fillfactor?
>
> ---------------------------------------------------------------------------
>
> Simon Riggs wrote:
> > A few minor typos/notes:
> >
> > INDEXES
> >
> > 1. On 2nd bullet...
> > "The main difficulty with this item is the problem of creating an index
> > that can spam more than one table."
> >
> > should be span, not spam
> >
> > 2. On 6th bullet
> > * "Use index to restrict rows returned by multi-key index when used
> > with non-consecutive keys to reduce heap accesses
> >
> > For an index on col1,col2,col3, and a WHERE clause of col1 = 5 and col3
> > = 9, spin though the index checking for col1 and col3 matches, rather
> > than just col1 "
> >
> > This is also known as "skip-scanning", so it would be good to use that
> > phrase in the TODO
> >
> > 3. Whatever happened to the FILLFACTOR todo item? AFAICS it disappeared
> > sometime at the beginning of August, but I'm not sure why?
> >
> > REF INTEGRITY
> >
> > ...Didn't we just get rid of deferred triggers?? Perhaps I read that
> > wrong.
> >
> >
> > CACHE
> >
> > 1. 1st bullet....prefix it with "Use posix_fadvise() API to let OS know
> > how files will be used by PostgreSQL. This would allow, for example,
> > a..." (replacing the word "add").
> >
> >
> >
> > --
> > Best Regards, Simon Riggs
> >
> >
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>
> --
> Bruce Momjian | http://candle.pha.pa.us
> pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 359-1001
> + If your life is a hard drive, | 13 Roberts Road
> + Christ can be your backup. | Newtown Square, Pennsylvania 19073
>
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