Date: Tue, 19 Dec 2023 10:09:39 -0600
From: Nathan Bossart <nathandbossart@gmail.com>
To: Nikita Malakhov <hukutoc@gmail.com>
Cc: Andrei Lepikhov <a.lepikhov@postgrespro.ru>,
	pgsql-hackers@postgresql.org
Subject: Re: introduce dynamic shared memory registry
Message-ID: <20231219160939.GC831499@nathanxps13>
References: <20231205034647.GA2705267@nathanxps13>
 <d725b5a7-5507-4630-9482-46f28c3bf0d1@postgrespro.ru>
 <3dcea2e9-c46d-4e4f-8371-9526d1aebc83@postgrespro.ru>
 <CAN-LCVMEM54iSLFANEne7eDjGCAipmn+1dDp67Jju7q2sxfHmw@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAN-LCVMEM54iSLFANEne7eDjGCAipmn+1dDp67Jju7q2sxfHmw@mail.gmail.com>
Archived-At: <https://www.postgresql.org/message-id/20231219160939.GC831499%40nathanxps13>
Precedence: bulk

On Mon, Dec 18, 2023 at 12:05:28PM +0300, Nikita Malakhov wrote:
> Just a suggestion - maybe it is worth adding a function for detaching the
> segment,
> for cases when we unload and/or re-load the extension?

Hm.  We don't presently have a good way to unload a library, but you can
certainly DROP EXTENSION, in which case you might expect the segment to go
away or at least be reset.  But even today, once a preloaded library is
loaded, it stays loaded and its shared memory remains regardless of whether
you CREATE/DROP extension.  Can you think of problems with keeping the
segment attached?

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