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Glenn Sullivan
 
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Default shared buffers - 10-25-2004 , 03:31 PM






Hi,

In the 7.4.5 version, the code is now trying to use a much larger
value for shared_buffers. I can certainly set this to a lower number
with the -B option. However, my guestion is:

What is the performance issue with setting shared_buffers to something like 45?

In doing some timing on my system, I cannot tell any difference with 45 versus 1000.
Perhaps I am looking at the wrong performance criteria.

Thanks,
Glenn


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Tom Lane
 
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Default Re: shared buffers - 10-25-2004 , 04:08 PM






Glenn Sullivan <glenn.sullivan (AT) varianinc (DOT) com> writes:
Quote:
What is the performance issue with setting shared_buffers to something like 45?
In doing some timing on my system, I cannot tell any difference with 45 versus 1000.
What are you timing exactly? Almost every benchmark I've ever seen is
much happier with shared_buffers of at least a few hundred. Otherwise
you spend too much time copying data between kernel and user space.

regards, tom lane

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