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Miller" , "Eric Dumazet" , "Jakub Kicinski" , "Paolo Abeni" , "Simon Horman" Message-Id: <4edf7abf-8f48-4433-98f0-2ed2d97a32f5@app.fastmail.com> In-Reply-To: References: <20260430085412.96961-1-marco.crivellari@suse.com> <8d1eff7b-3712-4039-87d6-028a4118e210@app.fastmail.com> <1e220a70-4318-49de-aaac-332c0a1cfab4@app.fastmail.com> Subject: Re: [RFC PATCH] xprtrdma: Move long delayed work on system_dfl_long_wq Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On Thu, Apr 30, 2026, at 11:04 AM, Frederic Weisbecker wrote: > Le Thu, Apr 30, 2026 at 10:05:52AM -0400, Chuck Lever a =C3=A9crit : >> Does the patch address a bug (work isn't getting rescheduled at >> all) or is it merely a minor optimization for certain platforms? >>=20 >> What's the user-visible issue that will be improved with this >> change? > > It's not a bug, it's an optimization power-wise and performance-wise > and also part of a bigger sanity change: > > - Long works have no reason to stick to a single CPU. If they are conv= erted to > be unbound, the scheduler can move them to relevant targets to optim= ize > performances and power consumption. Hence the new system_unbound_lon= g_wq. > The goal is to remove system_long_wq if none of its users rely on lo= cality. > > - Using queue_delayed_work() with a bound workqueue doesn't make any s= ense > since the target is completely random. The light dawns (for me). That's what I'd like to see in the commit mess= age. I don't have any technical objections to the code change. --=20 Chuck Lever