Skip site navigation (1) Skip section navigation (2)

Re: [PERFORM] stats on cursor and query execution troubleshooting

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Alban Médici (NetCentrex)" <amedici(at)fr(dot)netcentrex(dot)net>
Cc: pgsql-benchmarks(at)postgresql(dot)org, pgsql-performance(at)postgresql(dot)org
Subject: Re: [PERFORM] stats on cursor and query execution troubleshooting
Date: 2004-10-06 14:16:39
Message-ID: 25576.1097072199@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-benchmarkspgsql-performance
=?ISO-8859-1?Q?=22Alban_M=E9dici_=28NetCentrex=29=22?= <amedici(at)fr(dot)netcentrex(dot)net> writes:
> I'm looking for the statistic of memory,  CPU,  filesystem access while=20
> executing some regular SQL query,  and I want to compare them to
> same kind of results while executing a cursor function.

I think your second query is finding all the disk pages it needs in
kernel disk cache, because they were all read in by the first query.
This has little to do with cursor versus non cursor, and everything
to do with hitting recently-read data again.

			regards, tom lane

In response to

Responses

pgsql-performance by date

Next:From: Bill MontgomeryDate: 2004-10-06 15:45:30
Subject: Re: Excessive context switching on SMP Xeons
Previous:From: Alan StangeDate: 2004-10-06 13:11:50
Subject: Re: Excessive context switching on SMP Xeons

pgsql-benchmarks by date

Next:From: Alban Médici (NetCentrex)Date: 2004-10-08 08:47:42
Subject: Re: [PERFORM] stats on cursor and query execution troubleshooting
Previous:From: Alban Médici (NetCentrex)Date: 2004-10-06 10:15:31
Subject: stats on cursor and query execution troubleshooting

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group