Re: proposal: Set effective_cache_size to greater of .conf value, shared_buffers - Mailing list pgsql-hackers

From Andrew Dunstan
Subject Re: proposal: Set effective_cache_size to greater of .conf value, shared_buffers
Date
Msg-id 53695D3D.3030806@dunslane.net
Whole thread Raw
In response to Re: proposal: Set effective_cache_size to greater of .conf value, shared_buffers  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
On 05/06/2014 05:54 PM, Robert Haas wrote:
> On Tue, May 6, 2014 at 4:38 PM, Simon Riggs <simon@2ndquadrant.com> wrote:
>>   I read the code, think what to say and then say what I think, not
>> rely on dogma.
>>
>> I tried to help years ago by changing the docs on e_c_s, but that's
>> been mostly ignored down the years, as it is again here.
> Well, for what it's worth, I've encountered systems where setting
> effective_cache_size too low resulted in bad query plans, but I've
> never encountered the reverse situation.


I have encountered both. Recently I discovered that a client's 
performance problems were solved pretty instantly by reducing a 
ridiculously high setting down to something more reasonable (in this 
case about 50% of physical RAM is what we set it to).

cheers

andrew



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