public inbox for [email protected]  
help / color / mirror / Atom feed
From: Bertrand Drouvot <[email protected]>
To: Heikki Linnakangas <[email protected]>
Cc: Andres Freund <[email protected]>
Cc: [email protected] <[email protected]>
Subject: Re: PGPROC alignment (was Re: pgsql: Separate RecoveryConflictReasons from procsignals)
Date: Wed, 11 Feb 2026 10:58:41 +0000
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>
	<[email protected]>

Hi,

On Wed, Feb 11, 2026 at 12:03:51PM +0200, Heikki Linnakangas wrote:
> On 11/02/2026 06:40, Bertrand Drouvot wrote:
> > > With this, sizeof(PGPROC) == 864 without the explicit alignment to
> > > PG_CACHE_LINE_SIZE, and 896 with it.
> > 
> > I can see 876 -> 896 on my side:
> > 
> > /*    872      |       4 */    uint32 wait_event_info;
> > /* XXX 20-byte padding   */
> > 
> >                                 /* total size (bytes):  896 */
> >                               }
> 
> Interesting. I've attached 'pahole bin/postgres' output from my laptop. It's
> Linux on arm64.

Thanks!

Got it: I was using "-DCACHEDEBUG -DWAL_DEBUG -DLOCK_DEBUG -DDEBUG_DEADLOCK"
so that with LOCK_DEBUG in place then LWLock size is 32 bytes (vs 16 in your case).

Regards,

-- 
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com





view thread (22+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected], [email protected]
  Subject: Re: PGPROC alignment (was Re: pgsql: Separate RecoveryConflictReasons from procsignals)
  In-Reply-To: <[email protected]>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox