Subject: Re: checkpoints, proper config
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>, Alvaro Herrera
 <alvherre@2ndquadrant.com>
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From: Jim Nasby <Jim.Nasby@BlueTreble.com>
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Date: Fri, 11 Dec 2015 17:47:36 -0600
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On 12/10/15 7:20 PM, Tomas Vondra wrote:
>> I agree, but actually, what is the sense of checkpoint_warning?  I think
>> it was useful back when we didn't have log_checkpoints, but now that we
>> have detailed checkpoint logging I think it's pretty much useless noise.
>>
>
> Not entirely. The WARNING only triggers when you get below the 30s (or
> whatever value is set in the config) and explicitly warns you about
> doing checkpoints too often. log_checkpoints=on logs all checkpoints and
> you have to do further analysis on the data (and it's just LOG).

Agree, though I also find it pretty useless to set it significantly less 
than checkpoint_timeout in almost all cases. If you want ~5 minutes 
between checkpoints checkpoint_timeout=30 seconds is way too low to be 
useful. We should really change the default.
-- 
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com


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