Re: PGC_SIGHUP shared_buffers?

On 2/18/24 15:35, Andres Freund wrote:
> On 2024-02-18 17:06:09 +0530, Robert Haas wrote:
>> How many people set shared_buffers to something that's not a whole
>> number of GB these days?
> 
> I'd say the vast majority of postgres instances in production run with less
> than 1GB of s_b. Just because numbers wise the majority of instances are
> running on small VMs and/or many PG instances are running on one larger
> machine.  There are a lot of instances where the total available memory is
> less than 2GB.
> 
>> I mean I bet it happens, but in practice if you rounded to the nearest GB,
>> or even the nearest 2GB, I bet almost nobody would really care. I think it's
>> fine to be opinionated here and hold the line at a relatively large granule,
>> even though in theory people could want something else.
> 
> I don't believe that at all unfortunately.

Couldn't we scale the rounding, e.g. allow small allocations as we do 
now, but above some number always round? E.g. maybe >= 2GB round to the 
nearest 256MB, >= 4GB round to the nearest 512MB, >= 8GB round to the 
nearest 1GB, etc?

-- 
Joe Conway
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com