shared_memory_size_in_huge_pages is a preset configuration parameter reporting the number of huge pages needed for the main shared memory area, based on the specified huge_page_size.
shared_memory_size_in_huge_pages was added in PostgreSQL 15.
On Linux systems,
shared_memory_size_in_huge_pages is computed at runtime if huge pages are available.
If huge pages are not available, or on systems other than Linux, the reported value is always