Re: Different memory allocation strategy in Postgres 11?

On Fri, Oct 26, 2018 at 9:12 AM Thomas Kellerer <spam_eater(at)gmx(dot)net> wrote:

> I have a Postgres instance running on my Windows laptop for testing
> purposes.
>
> I typically configure "shared_buffers = 4096MB" on my 16GB system as
> sometimes when testing, it pays off to have a bigger cache.
>
> With Postgres 10 and earlier, the Postgres process(es) would only allocate
> that memory from the operating system when needed.
> So right after startup, it would only consume several hundred MB, not the
> entire 4GB
>
> However with Postgres 11 I noticed that it immediately grabs the complete
> memory configured for shared_buffers during startup.
>
> It's not really a big deal, but I wonder if that is an intentional change
> or a result from something else?
>

Do you have pg_prewarm in shared_preload_libraries?

Cheers,

Jeff