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Date:   Wed, 23 Nov 2022 23:01:00 +0100
From:   Pavel Machek <pavel@ucw.cz>
To:     Eric Blake <eblake@redhat.com>
Cc:     kernel list <linux-kernel@vger.kernel.org>, josef@toxicpanda.com,
        linux-block@vger.kernel.org, nbd@other.debian.org
Subject: Re: nbd: please don't spawn 16 threads when nbd is not even in use
Message-ID: <Y36YHNVmbozzSdxH@duo.ucw.cz>
References: <Y3y4+QqOlF00X9ET@duo.ucw.cz>
 <20221123200845.cuct5euvikqksojm@redhat.com>
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Hi!

> > I see this... and it looks like there are 16 workqueues before nbd is
> > even used. Surely there are better ways to do that?
>=20
> Yes, it would be nice to create a pool of workers that only spawns up
> threads when actual parallel requests are made.  Are you willing to
> help write the patch?

I was thinking more "only spawn a workqueue when nbd is opened" or so.

I have 16 of them, and I'm not using nbd. Workqueue per open device is
okay, current situation... not so much.

      	       	    	  	  	    	     		Pavel
--=20
People of Russia, stop Putin before his war on Ukraine escalates.

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