Re: cache reads vs. disk reads - Mailing list pgsql-general

From decibel
Subject Re: cache reads vs. disk reads
Date
Msg-id 003892BD-90F5-4D30-AB0F-B1A9D4220A13@decibel.org
Whole thread Raw
In response to cache reads vs. disk reads  (Gerd König <koenig@transporeon.com>)
List pgsql-general
On Jul 1, 2009, at 4:20 AM, Gerd König wrote:
> b) pg_statio_user_tables=>
>
> heap_blks_read is the number of disk blocks read for that table
> (excluding index
> access), does heap_blks_hit mean the number of accesses to the
> cache for that data ?
> ...and is the number of heap_blks_read in heap_blks_hit included,
> or is this
> number the additional accesses, after reading the data from disk to
> buffer ?


Take a look in the manual; there's a pretty clear explanation in there.
--
Decibel!, aka Jim C. Nasby, Database Architect  decibel@decibel.org
Give your computer some brain candy! www.distributed.net Team #1828



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