From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754602AbdL1U7g (ORCPT ); Thu, 28 Dec 2017 15:59:36 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:52460 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750854AbdL1U7f (ORCPT ); Thu, 28 Dec 2017 15:59:35 -0500 Date: Thu, 28 Dec 2017 21:59:33 +0100 From: Pavel Machek To: Ozgur Cc: Mike Galbraith , Thomas Gleixner , kernel list , "mingo@redhat.com" , "hpa@zytor.com" , "x86@kernel.org" , "peterz@infradead.org" Subject: Re: niced tasks on SMT system Message-ID: <20171228205933.GB20142@amd> References: <20171228121024.GA18152@amd> <1514467413.6886.35.camel@gmx.de> <20171228185354.GA3631@amd> <1150011514487512@web36o.yandex.ru> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="l76fUT7nc3MelDdI" Content-Disposition: inline In-Reply-To: <1150011514487512@web36o.yandex.ru> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --l76fUT7nc3MelDdI Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > >> =A0> Ok, so I'm compiling, and I'd like to run a flight simulator. > >> =A0> > >> =A0> Flightgear normally does 20fps on my system... kinda low but play= able. > >> =A0> > >> =A0> I have reniced make -j 5 fo kernel running. Scheduler gives 100% = of > >> =A0> one of CPUs to Flightgear (good), but the smt sibling is used by = the > >> =A0> compilation, and I'm down to 9 fps. Not good. > >> =A0> > >> =A0> Even with single-threaded make, I have 10-13fps. > >> =A0> > >> =A0> Is there way to learn which CPUs are SMT siblings? > >> > >> =A0cat /sys/devices/system/cpu/cpu{N}/topology/thread_siblings > > > > Thanks for a hint. > > > > Well, something is definitely wrong there: > > > > pavel@duo:/data/l/linux-n900$ cat > > /sys/devices/system/cpu/cpu0/topology/thread_siblings > > 03 >=20 > Ops, >=20 > do you fly on N900 via flightgear? :) > I have two N900 and one run gentoo. No, no flightgear on N900. It was preparing kernels for my N900 that interfered with flying. BTW there's lot of fun to be had with N900. https://wiki.postmarketos.org/wiki/Nokia_N900_(nokia-rx51) I even have voice calls working on Debian, help welcome :-). Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --l76fUT7nc3MelDdI Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlpFWzUACgkQMOfwapXb+vJRYACglrZzEEDefCb5BM67Cuf5vQOH DEUAoLQYUvbqTn0bLC8g9gh7jlqsWFOu =QJAw -----END PGP SIGNATURE----- --l76fUT7nc3MelDdI--