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Date: Wed, 4 Dec 2013 19:26:01 +0100
From: Andres Freund <andres@2ndquadrant.com>
To: Metin Doslu <metin@citusdata.com>
Cc: postgres performance list <pgsql-performance@postgresql.org>,
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Subject: Re: [HACKERS] Parallel Select query performance and shared buffers
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On 2013-12-04 20:19:55 +0200, Metin Doslu wrote:
> - When we increased NUM_BUFFER_PARTITIONS to 1024, this problem is
> disappeared for 8 core machines and come back with 16 core machines on
> Amazon EC2. Would it be related with PostgreSQL locking mechanism?

You could try my lwlock-scalability improvement patches - for some
workloads here, the improvements have been rather noticeable. Which
version are you testing?

Greetings,

Andres Freund

-- 
 Andres Freund	                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services


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