DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com;
	h=Message-ID:X-YMail-OSG:Received:X-Mailer:References:Date:From:Subject:To:Cc:In-Reply-To:MIME-Version:Content-Type;
	b=jB7uLAxt6A0ttu49dXdCqmZcb6y9blnSyu23doQ+PVB1fRHzTRMupcY+MDSSPFFfLyZHXERpwTYnaNBx5IykEsbQCV041VZPeqEWlkrPi8FUnRo1PdB2hLgpp23oemgW+OpLfhGXMwbZzg+TvWZkJrAN0SAjAXr7lR82buqV9vo=;
Message-ID: <529329.89885.qm@web120007.mail.ne1.yahoo.com>
References: <788866.21140.qm@web120020.mail.ne1.yahoo.com>
	<4C7D00330200002500034ED2@gw.wicourts.gov>
	<19320.56933.qm@web120013.mail.ne1.yahoo.com>
	<AANLkTi=6k6AbmBcqkVCKgNSiogVfQmP+iOC8FgA6+e5J@mail.gmail.com>
Date: Thu, 2 Sep 2010 09:12:59 -0700 (PDT)
From: A J <s5aly@yahoo.com>
Subject: Re: Confused by 'timing' results
To: Scott Marlowe <scott.marlowe@gmail.com>
Cc: Kevin Grittner <Kevin.Grittner@wicourts.gov>, pgsql-admin@postgresql.org
In-Reply-To: <AANLkTi=6k6AbmBcqkVCKgNSiogVfQmP+iOC8FgA6+e5J@mail.gmail.com>
MIME-Version: 1.0
Content-Type: multipart/alternative; boundary="0-503636566-1283443979=:89885"

--0-503636566-1283443979=:89885
Content-Type: text/plain; charset=us-ascii

I am conducting the test with several concurrent clients.
The problem I am now facing in using log_min_duration_statement is that all the 
clients have to write to a single log file in the pg_log directory. So they have 
to wait for the other writes to happen before completing their write. This seems 
to be reason why the measured duration in the log file (for several concurrent 
clients) is way more, infact much more than what was measured by psql timing 
from the client side.

(The problem with ssh tunnel and then psql on database server is that the 
database will think the connections are local. I want to mimic real-life where 
the tcp connections are opened directly by clients from different IPs.)

related settings:
log_destination = 'stderr'              # Valid values are combinations of
#log_directory = 'pg_log'               # directory where log files are written,
#log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log'        # log file name pattern,


________________________________
From: Scott Marlowe <scott.marlowe@gmail.com>
To: A J <s5aly@yahoo.com>
Cc: Kevin Grittner <Kevin.Grittner@wicourts.gov>; pgsql-admin@postgresql.org
Sent: Tue, August 31, 2010 4:02:33 PM
Subject: Re: [ADMIN] Confused by 'timing' results

On Tue, Aug 31, 2010 at 1:01 PM, A J <s5aly@yahoo.com> wrote:
> OK, thanks Kevin. So to measure just the time take by database server, I
> guess I need to set the log_min_duration_statement and log_statement
> parameters in postgresql.conf
> log_min_duration_statement output should stay constant for all the different
> clients across different geographic locations.

Also, if you want to test turn around time without the disk drives
being an issue, you can do "select 1" instead of "select * from table
(yada)"


--0-503636566-1283443979=:89885
Content-Type: text/html; charset=us-ascii

<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:'times new roman', 'new york', times, serif;font-size:12pt"><div>I am conducting the test with several concurrent clients.</div><div>The problem I am now facing in using log_min_duration_statement is that all the clients have to write to a single log file in the pg_log directory. So they have to wait for the other writes to happen before completing their write. This seems to be reason why the measured duration in the log file (for several concurrent clients) is way more, infact much more than what was measured by psql timing from the client side.</div><div><br></div><div>(The problem with ssh tunnel and then psql on database server is that the database will think the connections are local. I want to mimic real-life where the tcp connections are opened directly by clients from different IPs.)</div><div><br></div><div style="font-family:times new
 roman, new york, times, serif;font-size:12pt">related settings:</div><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><div>log_destination = 'stderr' &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;# Valid values are combinations of</div><div>#log_directory = 'pg_log' &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; # directory where log files are written,</div><div>#log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log' &nbsp; &nbsp; &nbsp; &nbsp;# log file name pattern,</div><div><br></div></div><div style="font-family:times new roman, new york, times, serif;font-size:12pt"><br><div style="font-family:arial, helvetica, sans-serif;font-size:13px"><font size="2" face="Tahoma"><hr size="1"><b><span style="font-weight: bold;">From:</span></b> Scott Marlowe &lt;scott.marlowe@gmail.com&gt;<br><b><span style="font-weight: bold;">To:</span></b> A J &lt;s5aly@yahoo.com&gt;<br><b><span style="font-weight: bold;">Cc:</span></b> Kevin
 Grittner &lt;Kevin.Grittner@wicourts.gov&gt;; pgsql-admin@postgresql.org<br><b><span style="font-weight: bold;">Sent:</span></b> Tue, August 31, 2010 4:02:33 PM<br><b><span style="font-weight: bold;">Subject:</span></b> Re: [ADMIN] Confused by 'timing' results<br></font><br>
On Tue, Aug 31, 2010 at 1:01 PM, A J &lt;<a ymailto="mailto:s5aly@yahoo.com" href="mailto:s5aly@yahoo.com">s5aly@yahoo.com</a>&gt; wrote:<br>&gt; OK, thanks Kevin. So to measure just the time take by database server, I<br>&gt; guess I need to set the&nbsp;log_min_duration_statement and log_statement<br>&gt; parameters in postgresql.conf<br>&gt; log_min_duration_statement output should stay constant for all the different<br>&gt; clients across different geographic locations.<br><br>Also, if you want to test turn around time without the disk drives<br>being an issue, you can do "select 1" instead of "select * from table<br>(yada)"<br></div></div><div style="position:fixed"></div>


</div><br>

      </body></html>
--0-503636566-1283443979=:89885--