Message-ID: <488D11CA.9070803@commandprompt.com>
Date: Sun, 27 Jul 2008 17:24:42 -0700
From: "Joshua D. Drake" <jd@commandprompt.com>
Organization: Command Prompt, Inc.
User-Agent: Thunderbird 2.0.0.16 (Windows/20080708)
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To: Andrew Dunstan <andrew@dunslane.net>
CC: Simon Riggs <simon@2ndquadrant.com>, Tom Lane <tgl@sss.pgh.pa.us>,
	Stephen Frost <sfrost@snowman.net>, pgsql-patches@postgresql.org
Subject: Re: pg_dump additional options for performance
References: <20080721115602.GG18846@tamriel.snowman.net>	
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	<1216885031.3894.739.camel@ebony.2ndQuadrant>	
	<21687.1216886041@sss.pgh.pa.us>	
	<1216889809.3894.747.camel@ebony.2ndQuadrant>	
	<2818.1217027784@sss.pgh.pa.us>	
	<1217063104.3894.1100.camel@ebony.2ndQuadrant>	
	<23540.1217089204@sss.pgh.pa.us>	
	<20080726164355.GH16005@tamriel.snowman.net>	
	<24327.1217094186@sss.pgh.pa.us>
	<1217095404.16378.184.camel@jd-laptop>
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	<488CA8ED.6080908@commandprompt.com>
	<488D07E0.4020303@dunslane.net>
In-Reply-To: <488D07E0.4020303@dunslane.net>
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Andrew Dunstan wrote:
> 
> 
> Joshua D. Drake wrote:
>>
>> Agreed but that is a problem I understand with a solution I don't. I 
>> am all eyes on a way to fix that. One thought I had and please, be 
>> gentle in response was some sort of async transaction capability. I 
>> know that libpq has the ability to send async queries. Is it possible 
>> to do this:
>>
>> send async(copy table to foo)
>> send async(copy table to bar)
>> send async(copy table to baz)
>>
>> Where all three copies are happening in the background?
>>
>>
> 
> IIRC, libpq doesn't let you have more than one async query active at one 
> time.

Now that I think on it harder, this isn't even a libpq problem (although 
its involved), we need the postmaster do be able to do a background 
async query. Which is (I am guessing) why libpq can only do one at a time.

Sincerely,

Joshua D. Drake