Re: introduce dynamic shared memory registry

Here's a new version of the patch set with Bharath's feedback addressed.

On Tue, Jan 02, 2024 at 11:31:14AM -0500, Robert Haas wrote:
> On Tue, Jan 2, 2024 at 11:21 AM Nathan Bossart <nathandbossart(at)gmail(dot)com> wrote:
>> > Are we expecting, for instance, a 128-bit UUID being used as a key and
>> > hence limiting it to a higher value 256 instead of just NAMEDATALEN?
>> > My thoughts were around saving a few bytes of shared memory space that
>> > can get higher when multiple modules using a DSM registry with
>> > multiple DSM segments.
>>
>> I'm not really expecting folks to use more than, say, 16 characters for the
>> key, but I intentionally set it much higher in case someone did have a
>> reason to use longer keys. I'll lower it to 64 in the next revision unless
>> anyone else objects.
>
> This surely doesn't matter either way. We're not expecting this hash
> table to have more than a handful of entries; the difference between
> 256, 64, and NAMEDATALEN won't even add up to kilobytes in any
> realistic scenario, let along MB or GB.

Right.

--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com