From owner-freebsd-stable@freebsd.org Mon Jan 22 01:00:37 2018 Return-Path: Delivered-To: freebsd-stable@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B6EAAEC57F5 for ; Mon, 22 Jan 2018 01:00:37 +0000 (UTC) (envelope-from truckman@FreeBSD.org) Received: from mx2.catspoiler.org (mx2.catspoiler.org [IPv6:2607:f740:16::d18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "amnesiac", Issuer "amnesiac" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 95093284 for ; Mon, 22 Jan 2018 01:00:37 +0000 (UTC) (envelope-from truckman@FreeBSD.org) Received: from gw.catspoiler.org ([76.212.85.177]) by mx2.catspoiler.org (8.15.2/8.15.2) with ESMTPS id w0M10wth089512 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 22 Jan 2018 01:00:59 GMT (envelope-from truckman@FreeBSD.org) Received: from mousie.catspoiler.org (mousie.catspoiler.org [192.168.101.2]) by gw.catspoiler.org (8.15.2/8.15.2) with ESMTPS id w0M0NREJ048750 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 21 Jan 2018 17:00:26 -0800 (PST) (envelope-from truckman@FreeBSD.org) Date: Sun, 21 Jan 2018 17:00:25 -0800 (PST) From: Don Lewis Subject: Re: Ryzen issues on FreeBSD ? To: Willem Jan Withagen cc: Pete French , freebsd-stable@freebsd.org In-Reply-To: <86eba4e4-f9a7-7177-a6bf-12700b1defa0@digiware.nl> Message-ID: References: <8e842dec-ade7-37d1-6bd8-856ea1a827ca@sentex.net> <8dcf6cc8fad788ac8168a4a9f392b02e@foolishgames.com> <23c1d162-dcd8-c422-3114-d70b65b6c271@sentex.net> <00875e4d-740f-63f1-496c-6cda82b1a403@ingresso.co.uk> <52744797-0606-44e7-72dd-242a6b56066a@digiware.nl> <86eba4e4-f9a7-7177-a6bf-12700b1defa0@digiware.nl> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=us-ascii Content-Disposition: INLINE X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 22 Jan 2018 01:00:37 -0000 On 21 Jan, Willem Jan Withagen wrote: > On 21/01/2018 21:24, Don Lewis wrote: >> On 21 Jan, Willem Jan Withagen wrote: >>> On 19/01/2018 23:29, Don Lewis wrote: >>>> On 19 Jan, Pete French wrote: >>>>> Out of interest, is there anyone out there running Ryzen who *hasnt* >>>>> seen lockups ? I'd be curious if there a lot of lurkers thinking "mine >>>>> works fine" >>>> >>>> No hangs or silent reboots here with either my original CPU or warranty >>>> replacement once the shared page fix was in place. >>> >>> Perhaps a too weird reference: >>> >>> I have supplied a customer with a Ryzen5 and a 350MB motherboard. >>> But he runs Windows 10, but I haven't heard him complain about anything >>> like this. >>> But I'll ask him specific. >> >> Only the BSDs were affected by the shared page issue. I think Linux >> already had a guard page. I don't think Windows was affected by the >> idle C-state issue. I suspect it is caused by software not doing the >> right thing during C-state transitions, but the publicly available >> documentation from AMD is pretty lacking. The random segfault issue is >> primarily triggered by heavy parallel software build loads and how many >> Windows users do that? > > This is an adobe workstation where several users remote login and do > work. So I would assume that the system is seriously (ab)used. > > Adn as expected I'm know aware of any of the detailed things that > Windows does while powering into lesser active states. It might depend on the scheduler details. On Linux and the FreeBSD ULE scheduler, runnable threads migrate between CPUs to balance the loading across all cores. When I did some experiments to disable that, the rate of build failures greatly decreased. AMD has been very vague about the cause of the problem (a "performance marginality") and resorted to replacing CPUs with this problem without suggesting any sort of software workaround.