Re: proposal: Set effective_cache_size to greater of .conf value, shared_buffers

On 05/07/2014 10:12 AM, Andres Freund wrote:
> On 2014-05-07 10:07:07 -0400, Tom Lane wrote:
>> In the meantime, it seems like there is an emerging consensus that nobody
>> much likes the existing auto-tuning behavior for effective_cache_size,
>> and that we should revert that in favor of just increasing the fixed
>> default value significantly.  I see no problem with a value of say 4GB;
>> that's very unlikely to be worse than the pre-9.4 default (128MB) on any
>> modern machine.
>>
>> Votes for or against?
> +1 for increasing it to 4GB and remove the autotuning. I don't like the
> current integration into guc.c much and a new static default doesn't
> seem to be worse than the current autotuning.
>
>


+1. If we ever want to implement an auto-tuning heuristic it seems we're 
going to need some hard empirical evidence to support it, and that 
doesn't seem likely to appear any time soon.

cheers

andrew