Received: from makus.postgresql.org (makus.postgresql.org [98.129.198.125])
	by mail.postgresql.org (Postfix) with ESMTP id 2FC0B9552D7
	for <pgsql-admin@postgresql.org>; Tue, 28 Feb 2012 18:57:13 -0400 (AST)
Received: from mail-pz0-f46.google.com ([209.85.210.46])
	by makus.postgresql.org with esmtp (Exim 4.72)
	(envelope-from <brianf@consistentstate.com>) id 1S2Vyr-00071A-0D
	for pgsql-admin@postgresql.org; Tue, 28 Feb 2012 22:57:13 +0000
Received: by daed14 with SMTP id d14so2868627dae.19
	for <pgsql-admin@postgresql.org>; Tue, 28 Feb 2012 14:56:59 -0800 (PST)
Received-SPF: pass (google.com: domain of brianf@consistentstate.com
	designates 10.68.225.194 as permitted sender)
	client-ip=10.68.225.194;
Authentication-Results: mr.google.com; spf=pass (google.com: domain of
	brianf@consistentstate.com designates 10.68.225.194 as
	permitted sender) smtp.mail=brianf@consistentstate.com
Received: from mr.google.com ([10.68.225.194])
	by 10.68.225.194 with SMTP id rm2mr59834613pbc.95.1330469819808
	(num_hops = 1); Tue, 28 Feb 2012 14:56:59 -0800 (PST)
Received: by 10.68.225.194 with SMTP id rm2mr50346888pbc.95.1330469819762;
	Tue, 28 Feb 2012 14:56:59 -0800 (PST)
Received: from sidon.consistentstate.com
	(173-164-51-9-colorado.hfc.comcastbusiness.net. [173.164.51.9])
	by mx.google.com with ESMTPS id g3sm16809619pbt.41.2012.02.28.14.56.58
	(version=SSLv3 cipher=OTHER); Tue, 28 Feb 2012 14:56:59 -0800 (PST)
Message-ID: <4F4D5AE0.9020204@consistentstate.com>
Date: Tue, 28 Feb 2012 15:53:20 -0700
From: Brian Fehrle <brianf@consistentstate.com>
User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US;
	rv:1.9.2.26) Gecko/20120129 Lightning/1.0b2 Thunderbird/3.1.18
MIME-Version: 1.0
To: pgsql-admin@postgresql.org
Subject: Hot standby having high requested checkpoints?
Content-Type: multipart/alternative;
	boundary="------------030602080107000105090900"
X-Gm-Message-State: 
 ALoCoQmkrwVNy3Yuhymu7OCvGgiRjnM7BN+/xgI9IWwgdVIw6+En9NKrW8AyCXnQLQKgQY0NmMXJ
X-Pg-Spam-Score: -2.6 (--)
X-Archive-Number: 201202/122
X-Sequence-Number: 39182

This is a multi-part message in MIME format.
--------------030602080107000105090900
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

Hi all,

I have two PostgreSQL 9.0.5 clusters, one is a master and the other is a 
hot standby via streaming replication. I'm monitoring some stats on each 
and I'm noticing something very odd. On the master, I get between 2 and 
4 requested checkpoints per hour, but on the hot standby I'm seeing 
between 200 and 300 requested checkpoints per hour.

Both boxes are the same specs, and have the same following config 
parameters:
              name             | setting
------------------------------+---------
  bgwriter_delay               | 200
  bgwriter_lru_maxpages        | 350
  bgwriter_lru_multiplier      | 2
  checkpoint_completion_target | 0.5
  checkpoint_segments          | 256
  checkpoint_timeout           | 1800


Is there any reason why I would be seeing this type of behavior on the 
hot standby? Is it the standard type of behavior on a hot standby that 
I'm only now noticing?

Thanks in advance,
- Brian F

--------------030602080107000105090900
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>

    <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">
  </head>
  <body text="#000000" bgcolor="#ffffff">
    Hi all,<br>
    <br>
    I have two PostgreSQL 9.0.5 clusters, one is a master and the other
    is a hot standby via streaming replication. I'm monitoring some
    stats on each and I'm noticing something very odd. On the master, I
    get between 2 and 4 requested checkpoints per hour, but on the hot
    standby I'm seeing between 200 and 300 requested checkpoints per
    hour. <br>
    <br>
    Both boxes are the same specs, and have the same following config
    parameters:<br>
    <font face="monospace">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; name&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | setting<br>
      ------------------------------+---------<br>
      &nbsp;bgwriter_delay&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | 200<br>
      &nbsp;bgwriter_lru_maxpages&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | 350<br>
      &nbsp;bgwriter_lru_multiplier&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | 2<br>
      &nbsp;checkpoint_completion_target | 0.5<br>
      &nbsp;checkpoint_segments&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | 256<br>
      &nbsp;checkpoint_timeout&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | 1800</font><br>
    <br>
    <br>
    Is there any reason why I would be seeing this type of behavior on
    the hot standby? Is it the standard type of behavior on a hot
    standby that I'm only now noticing?<br>
    <br>
    Thanks in advance,<br>
    - Brian F<br>
  </body>
</html>

--------------030602080107000105090900--