Re: crash-safe visibility map, take four

Simon Riggs <simon@2ndquadrant.com>

From: Simon Riggs <simon@2ndQuadrant.com>

To: Jesper Krogh <jesper@krogh.cc>

Cc: Robert Haas <robertmhaas@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>

Date: 2011-03-24T22:05:12Z

Lists: pgsql-hackers

On Wed, Mar 23, 2011 at 6:16 AM, Jesper Krogh <jesper@krogh.cc> wrote:
> On 2011-03-22 21:43, Robert Haas wrote:
>>
>> I took a crack at implementing the first approach described above,
>> which seems to be by far the simplest idea we've come up with to date.
>>  Patch attached.  It doesn't seem to be that complicated, which could
>> mean either that it's not that complicated or that I'm missing
>> something.  Feel free to point and snicker in the latter case.
>
> Looks simple, but there is now benefit...

Your tests and discussion remind me that I haven't yet seen any tests
that show that index-only scans would be useful for performance.

Everyone just seems to be assuming that they make a huge difference,
and that the difference is practically realisable in a common
workload.

Perhaps that's already been done and I just didn't notice?

-- 
 Simon Riggs                   http://www.2ndQuadrant.com/
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