From owner-freebsd-hackers@FreeBSD.ORG Fri Jan 20 01:07:48 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 52623106564A for ; Fri, 20 Jan 2012 01:07:48 +0000 (UTC) (envelope-from grog@lemis.com) Received: from w3.lemis.com (w3.lemis.com [208.86.224.149]) by mx1.freebsd.org (Postfix) with ESMTP id 222038FC0A for ; Fri, 20 Jan 2012 01:07:47 +0000 (UTC) Received: from dereel.lemis.com (1032.x.rootbsd.net [208.86.224.149]) by w3.lemis.com (Postfix) with ESMTP id ADA223B752; Fri, 20 Jan 2012 00:57:43 +0000 (UTC) Received: by dereel.lemis.com (Postfix, from userid 1004) id 70D38DADA8; Fri, 20 Jan 2012 11:57:42 +1100 (EST) Date: Fri, 20 Jan 2012 11:57:42 +1100 From: Greg 'groggy' Lehey To: Dieter BSD Message-ID: <20120120005742.GC41280@dereel.lemis.com> References: <20120119005820.218250@gmx.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="qtZFehHsKgwS5rPz" Content-Disposition: inline In-Reply-To: <20120119005820.218250@gmx.com> User-Agent: Mutt/1.4.2.3i Organization: The FreeBSD Project Phone: +61-3-5346-1370 Mobile: +61-418-838-708 WWW-Home-Page: http://www.FreeBSD.org/ X-PGP-Fingerprint: 9A1B 8202 BCCE B846 F92F 09AC 22E6 F290 507A 4223 Cc: freebsd-hackers@freebsd.org Subject: Re: Giant lock gone? (was: Re: ...focus, longevity, and lifecycle) X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 Jan 2012 01:07:48 -0000 --qtZFehHsKgwS5rPz Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wednesday, 18 January 2012 at 19:58:19 -0500, Dieter BSD wrote: >> The original goal for 5.0 was to completely remove the Giant lock (and >> do other cool SMP-related stuff). Eventually it was realized that this >> was too big a goal to fully accomplish in 5.0 (albeit too late in the >> process) and the goal was changed to do the basic framework for the new >> SMP model; and lay the groundwork for "some things run under Giant for >> now, and we'll remove it from them ASAP." That actually turned out to >> last through 6, making 7 the realization of what 5.0 was supposed to be. > > So you are saying that the Giant lock was completely removed in 7.0? Giant is still there in 9.0. It's a pity you didn't say who you were quoting there. To my knowledge we never intended to completely remove Giant in 5.x. We realised from the start that it would take a long time. See http://www.lemis.com/grog/diary-jun2000.php for what we decided 12 years ago. Point 6 suggests removing the "Giant Kernel Spinlock", but that is misleading. We did that, and we gave the name Giant to the "blocking mutex for the kernel". Previously Giant didn't have a name, because it was the only one. Greg -- Sent from my desktop computer Finger grog@FreeBSD.org for PGP public key. See complete headers for address and phone numbers. This message is digitally signed. If your Microsoft MUA reports problems, please read http://tinyurl.com/broken-mua --qtZFehHsKgwS5rPz Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (FreeBSD) iEYEARECAAYFAk8YvAYACgkQIubykFB6QiMvIQCeJG27exCl4f899zmB+tGy42PR K+wAn3use1P01BSC7CYavchCMgIFdMmK =XaTK -----END PGP SIGNATURE----- --qtZFehHsKgwS5rPz--