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Date: Fri, 24 Jun 2011 13:55:47 -0500
From: Shaun Thomas <sthomas@peak6.com>
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To: Greg Smith <greg@2ndQuadrant.com>
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Subject: Re: Cost of creating an emply WAL segment
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On 06/24/2011 11:18 AM, Greg Smith wrote:

> sync=14525.296 s, total=14786.868 s

Whaaaaaaaaat!? 6% of 8GB is just shy of 500MB. That's not a small 
amount, exactly, but it took 14525 seconds to call syncs for those 
writes? What kind of ridiculous IO would cause something like that? 
That's even way beyond an OS-level dirty buffer flush on a massive 
system. Wow!

-- 
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 800 | Chicago IL, 60604
312-676-8870
sthomas@peak6.com

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