Date: Thu, 19 Dec 2024 06:12:04 +0000
From: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
To: Michael Paquier <michael@paquier.xyz>
Cc: Nazir Bilal Yavuz <byavuz81@gmail.com>,
	Alvaro Herrera <alvherre@alvh.no-ip.org>,
	Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
	pgsql-hackers@lists.postgresql.org
Subject: Re: per backend I/O statistics
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Hi,

On Thu, Dec 19, 2024 at 01:21:54PM +0900, Michael Paquier wrote:
> 
> While doing more tests with backends exiting concurrently with their
> stats scanned, I have detected one path in pg_stat_get_backend_io()
> after calling pgstat_get_beentry_by_proc_number() where we should also
> check that it does not return NULL, or we would crash on a pointer
> dereference when reading the backend type.
> 
> Fixed that,

Oh right, indeed all the others pgstat_get_beentry_by_proc_number() callers are
checking for a NULL returned value.

> bumped the two version counters, and done.

Thanks!

I think I'll start a dedicated thread to discuss the stats_fetch_consistency/'snapshot'
point (will be easier to follow than resuming the discussion in this thread).

Regards,

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