Re: Estimating HugePages Requirements?

On 9/13/21, 5:49 PM, "Kyotaro Horiguchi" <horikyota(dot)ntt(at)gmail(dot)com> wrote:
> At Tue, 14 Sep 2021 00:30:22 +0000, "Bossart, Nathan" <bossartn(at)amazon(dot)com> wrote in
>> On 9/13/21, 1:25 PM, "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> > Seems like "huge_pages_needed_for_shared_memory" would be sufficient.
>>
>> I think we are down to either shared_memory_size_in_huge_pages or
>> huge_pages_needed_for_shared_memory. Robert's argument against
>> huge_pages_needed_for_shared_memory was that it might sound like only
>> part of shared memory uses huge pages and we're only giving the number
>> required for that. Speaking of which, isn't that technically true?
>> For shared_memory_size_in_huge_pages, the intent is to make it sound
>> like we are providing shared_memory_size in terms of the huge page
>> size, but I think it could also be interpreted as "the amount of
>> shared memory that is currently stored in huge pages."
>>
>> I personally lean towards huge_pages_needed_for_shared_memory because
>> it feels the most clear and direct to me. I'm not vehemently opposed
>> to shared_memory_size_in_huge_pages, though. I don't think either one
>> is too misleading.
>
> I like 'in' slightly than 'for' in this context. I stand by Michael
> that that name looks somewhat too long especially considering that
> that name won't be completed on shell command lines, but won't fight
> it, too. On the other hand the full-spelled name can be thought as
> one can spell it out from memory easily than a name halfway shortened.

I think I see more support for shared_memory_size_in_huge_pages than
for huge_pages_needed_for_shared_memory at the moment. I'll update
the patch set in the next day or two to use
shared_memory_size_in_huge_pages unless something changes in the
meantime.

Nathan