Date: Tue, 19 Dec 2023 10:19:11 -0600
From: Nathan Bossart <nathandbossart@gmail.com>
To: Michael Paquier <michael@paquier.xyz>
Cc: pgsql-hackers@postgresql.org
Subject: Re: introduce dynamic shared memory registry
Message-ID: <20231219161911.GE831499@nathanxps13>
References: <20231205034647.GA2705267@nathanxps13>
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On Fri, Dec 08, 2023 at 04:36:52PM +0900, Michael Paquier wrote:
> Yes, tracking that in a more central way can have many usages, so your
> patch sounds like a good idea.  Note that we have one case in core
> that be improved and make use of what you have here: autoprewarm.c.

I'll add a patch for autoprewarm.c.  Even if we don't proceed with that
change, it'll be a good demonstration.

> +dsm_registry_init_or_attach(const char *key, void **ptr, size_t size,
> +                           void (*init_callback) (void *ptr))
> 
> This is shaped around dshash_find_or_insert(), but it looks like you'd
> want an equivalent for dshash_find(), as well.

What is the use-case for only verifying the existence of a segment?

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com