From owner-freebsd-current@FreeBSD.ORG Tue May 9 01:11:15 2006 Return-Path: X-Original-To: current@FreeBSD.org Delivered-To: freebsd-current@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6B30116A45A; Tue, 9 May 2006 01:11:15 +0000 (UTC) (envelope-from kris@obsecurity.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7B25043D6E; Tue, 9 May 2006 01:11:10 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196]) by elvis.mu.org (Postfix) with ESMTP id 5AA501A3C1F; Mon, 8 May 2006 18:11:10 -0700 (PDT) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id B566651742; Mon, 8 May 2006 21:11:09 -0400 (EDT) Date: Mon, 8 May 2006 21:11:09 -0400 From: Kris Kennaway To: Kris Kennaway Message-ID: <20060509011109.GA57060@xor.obsecurity.org> References: <20060506150622.C17611@fledge.watson.org> <20060506221908.GB51268@xor.obsecurity.org> <20060507210426.GA4422@xor.obsecurity.org> <20060507214153.GA5275@xor.obsecurity.org> <20060507230430.GA6872@xor.obsecurity.org> <20060508065207.GA20386@xor.obsecurity.org> <20060509004328.GB55852@xor.obsecurity.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="OXfL5xGRrasGEqWY" Content-Disposition: inline In-Reply-To: <20060509004328.GB55852@xor.obsecurity.org> User-Agent: Mutt/1.4.2.1i Cc: performance@FreeBSD.org, Robert Watson , current@FreeBSD.org Subject: Re: Fine-grained locking for POSIX local sockets (UNIX domain sockets) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 May 2006 01:11:16 -0000 --OXfL5xGRrasGEqWY Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, May 08, 2006 at 08:43:28PM -0400, Kris Kennaway wrote: > On Mon, May 08, 2006 at 02:52:07AM -0400, Kris Kennaway wrote: > > OK, David's patch fixes the umtx thundering herd (and seems to give a > > 4-6% boost). I also fixed a thundering herd in FILEDESC_UNLOCK (which > > was also waking up 2-7 CPUs at once about 30% of the time) by doing > > s/wakeup/wakeup_one/. This did not seem to give a performance impact > > on this test though. >=20 > Turning down kern.hz from 1000 to 100 also made a big difference on 12 > CPUs (+6.1%). >=20 > Note also that the system is no less than 40% idle during the runs (at > any load), so the bottlenecks are serious. top -H shows the threads mostly in umtx state. Kris --OXfL5xGRrasGEqWY Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (FreeBSD) iD8DBQFEX+wtWry0BWjoQKURApXBAKDG+HoSkP+edodHh+glPxAYokNvtgCg0KQ8 ACuFSrfTnqu3yauVgzLaCCM= =paPx -----END PGP SIGNATURE----- --OXfL5xGRrasGEqWY--