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[82.69.141.171]) by smtp.gmail.com with ESMTPSA id t195sm30453419wme.13.2016.01.21.07.18.56 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 21 Jan 2016 07:18:58 -0800 (PST) Subject: Re: svn commit: r294329 - in head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs: . sys To: Slawa Olhovchenkov , alan somers References: <201601191700.u0JH0P6k061610@repo.freebsd.org> <569E6DA0.9010300@pix.net> <569F516D.80303@FreeBSD.org> <56A019A1.4030900@FreeBSD.org> <20160121113813.GG37895@zxy.spb.ru> <20160121151010.GH37895@zxy.spb.ru> Cc: "svn-src-head@freebsd.org" , "svn-src-all@freebsd.org" , "src-committers@freebsd.org" , Alan Somers , Andriy Gapon From: Steven Hartland Message-ID: <56A0F6E5.2020406@multiplay.co.uk> Date: Thu, 21 Jan 2016 15:19:01 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <20160121151010.GH37895@zxy.spb.ru> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.20 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: Thu, 21 Jan 2016 15:19:03 -0000 On 21/01/2016 15:10, Slawa Olhovchenkov wrote: > On Thu, Jan 21, 2016 at 08:03:25AM -0700, alan somers wrote: > >> On Thu, Jan 21, 2016 at 4:38 AM, Slawa Olhovchenkov wrote: >>> On Thu, Jan 21, 2016 at 01:34:57AM +0200, Andriy Gapon wrote: >>> >>>> On 20/01/2016 22:03, Alan Somers wrote: >>>>> On Wed, Jan 20, 2016 at 2:20 AM, Andriy Gapon wrote: >>>>>> On 19/01/2016 19:20, Alan Somers wrote: >>>>>>> The thing is, it never really worked in the first place. Panics and >>>>>>> deadlocks are so frequent that I don't think the feature was usable >>>>>>> for anybody. >>>>>> The feature is perfectly usable for me. I have never run into the problems that >>>>>> you describe. Why not fix the real bugs that you've run into? >>>>> Spectra Logic and iXSystems both experienced many problems with this. >>>>> The worst is a deadlock that can be triggered simply by pulling a >>>>> drive from a redundant pool when there exists a zvol anywhere in the >>>>> system (see https://reviews.freebsd.org/D4998 for a quick way to >>>>> reproduce). Fixing it correctly would likely require far more time >>>>> than I have available. I just want the bugs to go away. See that >>>>> same code review for a change to make the feature optional. >>>> I think that we all want all the bugs to go way. One way to remove bugs is to >>>> remove (disable) code that contains bugs. That way the perfect bug-free >>>> software is clearly achievable :-) Unfortunately, that technique is not always >>>> welcomed. >>>> >>>> P.S. >>>> I think that the real problem here is that a method of a geom must never drop >>>> topology_lock. In other words, the GEOM management code (like g_xxx() stuff in >>>> geom_subr.c) expects that a topology can not change underneath it. But >>>> zvol_geom_access() clearly breaks that contract. >>> May be same cause problem with swap on zvol (don't test on latest >>> -stable)? >> I'm not familiar with that problem. Is there a PR? > I am find PR 199189. > My expirense slightly different: VirtualBox VM with test install (384M > RAM) hang, not crashed, just infinite wait somewhere. Tested on 10.1. > Had the same on 10.2 last night.