From owner-freebsd-current@freebsd.org Mon Feb 19 02:43:19 2018 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id C70A2F1F0BF for ; Mon, 19 Feb 2018 02:43:19 +0000 (UTC) (envelope-from julian@freebsd.org) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 678EA7A968 for ; Mon, 19 Feb 2018 02:43:19 +0000 (UTC) (envelope-from julian@freebsd.org) Received: by mailman.ysv.freebsd.org (Postfix) id 2C1AEF1F0BA; Mon, 19 Feb 2018 02:43:19 +0000 (UTC) Delivered-To: current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 180B1F1F0B9 for ; Mon, 19 Feb 2018 02:43:19 +0000 (UTC) (envelope-from julian@freebsd.org) Received: from vps1.elischer.org (vps1.elischer.org [204.109.63.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "vps1.elischer.org", Issuer "CA Cert Signing Authority" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id ABD137A963; Mon, 19 Feb 2018 02:43:18 +0000 (UTC) (envelope-from julian@freebsd.org) Received: from Julian-MBP3.local (203-59-173-201.dyn.iinet.net.au [203.59.173.201]) (authenticated bits=0) by vps1.elischer.org (8.15.2/8.15.2) with ESMTPSA id w1J2ghXt028170 (version=TLSv1.2 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Sun, 18 Feb 2018 18:42:46 -0800 (PST) (envelope-from julian@freebsd.org) Subject: Re: Since last week (today) current on my Ryzen box is unstable To: Gleb Smirnoff , Andriy Gapon Cc: Andrew Reilly , kib@FreeBSD.org, current@FreeBSD.org References: <0CEA9D55-D488-42EC-BBDE-D0B7CE58BAEA@bigpond.net.au> <20180218023545.GE93303@FreeBSD.org> <431f3e00-c66a-8e2e-6c61-a315a6353d1d@FreeBSD.org> <20180218132623.GF93303@FreeBSD.org> <359681a7-3885-820e-1ac8-19254c83d1ad@FreeBSD.org> <20180218203358.GG93303@FreeBSD.org> From: Julian Elischer Message-ID: <5c03d74d-1c81-ec63-a4ae-4243141bf3c9@freebsd.org> Date: Mon, 19 Feb 2018 10:42:37 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180218203358.GG93303@FreeBSD.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.25 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: Mon, 19 Feb 2018 02:43:19 -0000 On 19/2/18 4:33 am, Gleb Smirnoff wrote: > On Sun, Feb 18, 2018 at 10:15:24PM +0200, Andriy Gapon wrote: > A> On 18/02/2018 15:26, Gleb Smirnoff wrote: > A> > My only point is that it is a performance improvement. IMHO that's enough :) > A> > A> I don't think that passing an invalid argument to a documented KPI is "enough" > A> for any optimization. > > I don't see a sense in making this KPI so sacred. This is something used internally > in kernel, and not used outside. The KPI has changed several times in the past. > > A> > If you can't suggest a more elegant way of doing that improvement, then all > A> > I can suggest is to document it and add its support to ZFS. > A> > A> In return I can only suggest that (1) you run your suggestion by arch@ -- unless > A> that's already been done and you can point me to the discussion, (2) document > A> it and (3) double-check that all implementations confirm to it. > > I can provide a patch for ZFS. > If any module outside of the code that implements it needs to know about it, then it is in the KPI and should be documented in the KPI documentation (e.g. man 9) Since the Filesystems need to know about this, it must be an externally visible feature and therefore needs to be documented.