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Subject: Re: Advice/guideline on increasing shared_buffers and kernel
	parameters
Date: Thu, 10 May 2012 14:02:56 +0530
Organization: Zoniac Software Private Limited
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> A formula which has held up pretty well across a lot of benchmarks 
> for years is that for optimal throughput the number of active 
> connections should be somewhere near 
> ((core_count * 2) + effective_spindle_count).

Our entire Production application stack is setup in Amazon EC2 cloud
environment, that includes database server also.  So, in that case, how do I
find out "effective_spindle_count"?  I know "core_count" can be determined
from Amazon EC2 instance type.  Per Amazon EC2, EBS volumes are reportedly a
shared resource.