Re: scan_recycle_buffers - Mailing list pgsql-patches

From Jeff Davis
Subject Re: scan_recycle_buffers
Date
Msg-id 1173485615.23455.7.camel@dogma.v10.wvs
Whole thread Raw
In response to Re: scan_recycle_buffers  ("Simon Riggs" <simon@2ndquadrant.com>)
List pgsql-patches
On Fri, 2007-03-09 at 20:37 +0000, Simon Riggs wrote:
> > I wonder if calling RelationGetNumberOfBlocks on every seq scan becomes
> > a performance issue for tiny tables with for example just 1 page. It
> > performs an lseek, which isn't free.
>
> Jeff's patch does this also, for similar reasons.
>

As Tom pointed out, the value is already in memory by the time it gets
to my code. My code just reads that value from memory.

Regards,
    Jeff Davis


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