Re:Re: how to know whether query data from memory after pg_prewarm - Mailing list pgsql-general

From jimmy
Subject Re:Re: how to know whether query data from memory after pg_prewarm
Date
Msg-id 335383.69c1.166146dba32.Coremail.mpokky@126.com
Whole thread Raw
In response to Re: how to know whether query data from memory after pg_prewarm  (Cédric Villemain <cedric@2ndQuadrant.com>)
List pgsql-general
But I use windows server 2012R.
pgfincore can not run on the windows.
Is there some replacements in windows system?






At 2018-09-19 15:44:06, "Cédric Villemain" <cedric@2ndQuadrant.com> wrote: >Le 19/09/2018 à 05:29, Thomas Munro a écrit : >> On Wed, Sep 19, 2018 at 1:35 PM jimmy <mpokky@126.com> wrote: >>> I use select pg_prewarm('table1','read','main') to load data of table1 into the memory. >>> when I use select count(1) from table1 group by aa to query data. >>> I find the speed of query is not fast, I wonder whether it query data from memory. >>> And it is slower than Oracle, both of Oracle and Postgresql has same table and count of data. >>> when pg_prewarm use 'read' mode, the data is put into the OS cache, how to examine the table which is pg_prewarmed into the OS cache . >>> I know pg_buffercache ,but it just examine the table in the shared buffer of Postgresql, not the table in the OS cache. >> >> This is a quick and dirty hack, but it might do what you want: >> >> https://github.com/macdice/pgdata_mincore >> >> Tested on FreeBSD, not sure how well it'll travel. > >You can use pgfincore extension for that purpose, and more. > >https://github.com/klando/pgfincore/blob/master/README.md > > >-- >Cédric Villemain +33 (0)6 20 30 22 52 >http://2ndQuadrant.fr/ >PostgreSQL: Support 24x7 - Développement, Expertise et Formation


 

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