From owner-svn-src-all@freebsd.org Fri Jan 31 04:05:38 2020 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 0C5A3231CC8; Fri, 31 Jan 2020 04:05:38 +0000 (UTC) (envelope-from cy.schubert@cschubert.com) Received: from smtp-out-no.shaw.ca (smtp-out-no.shaw.ca [64.59.134.9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "Client", Issuer "CA" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4883Xx4Hy5z4494; Fri, 31 Jan 2020 04:05:37 +0000 (UTC) (envelope-from cy.schubert@cschubert.com) Received: from spqr.komquats.com ([70.67.125.17]) by shaw.ca with ESMTPA id xNYjiT9xBnCigxNYkiolBG; Thu, 30 Jan 2020 21:05:35 -0700 X-Authority-Analysis: v=2.3 cv=cZisUULM c=1 sm=1 tr=0 a=VFtTW3WuZNDh6VkGe7fA3g==:117 a=VFtTW3WuZNDh6VkGe7fA3g==:17 a=kj9zAlcOel0A:10 a=Jdjhy38mL1oA:10 a=6I5d2MoRAAAA:8 a=YxBL1-UpAAAA:8 a=isZTVz-eGo4FwaFr8wAA:9 a=CjuIK1q_8ugA:10 a=IjZwj45LgO3ly-622nXo:22 a=Ia-lj3WSrqcvXOmTRaiG:22 Received: from slippy.cwsent.com (slippy [10.1.1.91]) by spqr.komquats.com (Postfix) with ESMTPS id 3FEB42BA; Thu, 30 Jan 2020 20:05:32 -0800 (PST) Received: from slippy.cwsent.com (localhost [127.0.0.1]) by slippy.cwsent.com (8.15.2/8.15.2) with ESMTP id 00V45VIV014120; Thu, 30 Jan 2020 20:05:31 -0800 (PST) (envelope-from Cy.Schubert@cschubert.com) Received: from slippy (cy@localhost) by slippy.cwsent.com (8.15.2/8.15.2/Submit) with ESMTP id 00V45VZn014071; Thu, 30 Jan 2020 20:05:31 -0800 (PST) (envelope-from Cy.Schubert@cschubert.com) Message-Id: <202001310405.00V45VZn014071@slippy.cwsent.com> X-Authentication-Warning: slippy.cwsent.com: cy owned process doing -bs X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7.1 Reply-to: Cy Schubert From: Cy Schubert X-os: FreeBSD X-Sender: cy@cwsent.com X-URL: http://www.cschubert.com/ To: Jeff Roberson cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r357314 - in head/sys: conf kern sys vm In-reply-to: <202001310049.00V0np1a077223@repo.freebsd.org> References: <202001310049.00V0np1a077223@repo.freebsd.org> Comments: In-reply-to Jeff Roberson message dated "Fri, 31 Jan 2020 00:49:51 +0000." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Thu, 30 Jan 2020 20:05:31 -0800 X-CMAE-Envelope: MS4wfC+ZVu+YgYELcq2xwbrl3P75Qln9VpHP+0bRom7m5KE0sGTcjuFK2FsFaAbPlOuEdYtDaPjjSFeap2nrRxAJL7BBUHPrhq5NgABtqSdeq4Iozqcn0LDL hIrFg8uQMX8pY1M9QVHDSQz0ExSCRKAwoJoZWf8/Vzv8sEe8IA3iKgrnS8fQ1coRzvOMaz1KHJgAsIgDvG4B9sUEb1tNk+sohO99gJmOptPfkQvvsRT8MVPG ukMzOYJOIWaNvyD9zPS+xNv7KUA0PKHWQFKzS4x5F7cRe/EjcZDc9OB5plwviE/V X-Rspamd-Queue-Id: 4883Xx4Hy5z4494 X-Spamd-Bar: ----- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-6.00 / 15.00]; NEURAL_HAM_MEDIUM(-1.00)[-0.999,0]; REPLY(-4.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000,0] X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 31 Jan 2020 04:05:38 -0000 In message <202001310049.00V0np1a077223@repo.freebsd.org>, Jeff Roberson writes : > Author: jeff > Date: Fri Jan 31 00:49:51 2020 > New Revision: 357314 > URL: https://svnweb.freebsd.org/changeset/base/357314 > > Log: > Implement a safe memory reclamation feature that is tightly coupled with UM > A. > > This is in the same family of algorithms as Epoch/QSBR/RCU/PARSEC but is > a unique algorithm. This has 3x the performance of epoch in a write heavy > workload with less than half of the read side cost. The memory overhead > is significantly lessened by limiting the free-to-use latency. A synthetic > test uses 1/20th of the memory vs Epoch. There is significant further > discussion in the comments and code review. > > This code should be considered experimental. I will write a man page after > it has settled. After further validation the VM will begin using this > feature to permit lockless page lookups. > > Both markj and cperciva tested on arm64 at large core counts to verify > fences on weaker ordering architectures. I will commit a stress testing > tool in a follow-up. > > Reviewed by: mmacy, markj, rlibby, hselasky > Discussed with: sbahara > Differential Revision: https://reviews.freebsd.org/D22586 > > Added: > head/sys/kern/subr_smr.c (contents, props changed) > head/sys/sys/_smr.h (contents, props changed) > head/sys/sys/smr.h (contents, props changed) > Modified: > head/sys/conf/files > head/sys/vm/uma.h > head/sys/vm/uma_core.c > head/sys/vm/uma_int.h > Thank you for all your hard work Jeff. -- Cheers, Cy Schubert FreeBSD UNIX: Web: http://www.FreeBSD.org The need of the many outweighs the greed of the few.