Horton

Re: making relfilenodes 56 bits

Alvaro Herrera <alvherre@alvh.no-ip.org>

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From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Dilip Kumar <dilipbalaut@gmail.com>, Andres Freund <andres@anarazel.de>, Heikki Linnakangas <hlinnaka@iki.fi>, Thomas Munro <thomas.munro@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, vignesh C <vignesh21@gmail.com>
Date: 2022-07-29T18:12:53Z
Lists: pgsql-hackers 
On 2022-Jul-29, Robert Haas wrote:

> I was taught that when programming in C one should avoid returning a
> struct type, as BufTagGetRelFileLocator does.

Doing it like that helps RelFileLocatorSkippingWAL, which takes a bare
RelFileLocator as argument.  With this coding you can call one function
with the other function as its argument.

However, with the current definition of relpathbackend() and siblings,
it looks quite disastrous -- BufTagGetRelFileLocator is being called
three times.  You could argue that a solution would be to turn those
macros into static inline functions.

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/
"I'm impressed how quickly you are fixing this obscure issue. I came from 
MS SQL and it would be hard for me to put into words how much of a better job
you all are doing on [PostgreSQL]."
 Steve Midgley, http://archives.postgresql.org/pgsql-sql/2008-08/msg00000.php

Commits

  1. Fix typos in comments, code and documentation

  2. Increase width of RelFileNumbers from 32 bits to 56 bits.

  3. Move RelFileNumber declarations to common/relpath.h.

  4. Include RelFileLocator fields individually in BufferTag.

  5. Convert macros to static inline functions (buf_internals.h)

  6. Remove the restriction that the relmap must be 512 bytes.

  7. Change internal RelFileNode references to RelFileNumber or RelFileLocator.

  8. Reorder subskiplsn in pg_subscription to avoid alignment issues.

  9. Fix DROP {DATABASE,TABLESPACE} on Windows.

  10. Restructure smgr API as per recent proposal. smgr no longer depends on