Re: XID formatting and SLRU refactorings (was: Add 64-bit XIDs into PostgreSQL 15) - Mailing list pgsql-hackers

On Thu, Jul 11, 2024 at 01:11:05PM +0300, Aleksander Alekseev wrote:
> Thanks, Michael. I prepared a corrected patchset.

A comment about v3-0001.

-     * If true, use long segment filenames formed from lower 48 bits of the
-     * segment number, e.g. pg_xact/000000001234. Otherwise, use short
-     * filenames formed from lower 16 bits of the segment number e.g.
-     * pg_xact/1234.
+     * If true, use long segment filenames. Use short filenames otherwise.
+     * See SlruFileName().

We're losing some details here even if SlruFileName() has some
explanations, because one would need to read through the snprintf's
04X to know that short file names include 4 characters.  I'm OK to
mention SlruFileName() rather than duplicate the knowledge here, but
SlruFileName() should also be updated to mention the same level of
details with some examples of file names.
--
Michael