From owner-freebsd-ports@FreeBSD.ORG Tue Nov 8 09:24:17 2005 Return-Path: X-Original-To: freebsd-ports@FreeBSD.ORG Delivered-To: freebsd-ports@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 06C0C16A41F; Tue, 8 Nov 2005 09:24:16 +0000 (GMT) (envelope-from sos@FreeBSD.ORG) Received: from spider.deepcore.dk (cpe.atm2-0-53484.0x50a6c9a6.abnxx9.customer.tele.dk [80.166.201.166]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3AC8B43D45; Tue, 8 Nov 2005 09:24:16 +0000 (GMT) (envelope-from sos@FreeBSD.ORG) Received: from [194.192.25.136] (mac.deepcore.dk [194.192.25.136]) by spider.deepcore.dk (8.13.4/8.13.3) with ESMTP id jA89NiC6039763; Tue, 8 Nov 2005 10:23:44 +0100 (CET) (envelope-from sos@FreeBSD.ORG) In-Reply-To: <20051108101608.2nucv3s9us4k844k@netchild.homeip.net> References: <20051106.131413.122956532.yasu@utahime.org> <1131176568.3960.20.camel@shumai.marcuscom.com> <20051106.131413.122956532.yasu@utahime.org> <20051107111800.e199ndcxa8s0c444@netchild.homeip.net> <20051107122458.27a1f9e7@it.buh.tecnik93.com> <20051107145645.rav7hhtlsggk4sss@netchild.homeip.net> <20051107214458.30ca47f2@it.buh.tecnik93.com> <20051108101608.2nucv3s9us4k844k@netchild.homeip.net> Mime-Version: 1.0 (Apple Message framework v746.2) X-Priority: 3 (Normal) Content-Type: text/plain; charset=ISO-8859-1; delsp=yes; format=flowed Message-Id: Content-Transfer-Encoding: quoted-printable From: =?ISO-8859-1?Q?S=F8ren_Schmidt?= Date: Tue, 8 Nov 2005 10:24:01 +0100 To: Alexander Leidinger X-Mailer: Apple Mail (2.746.2) X-mail-scanned: by DeepCore Virus & Spam killer v1.12 Cc: Ion-Mihai Tetcu , freebsd-ports@FreeBSD.ORG, le@FreeBSD.ORG Subject: Re: vinum, 5.x performance, ... (was: Re: ANNOUNCE: GNOME 2.12.1 has been merged into the ports tree) X-BeenThere: freebsd-ports@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Porting software to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 08 Nov 2005 09:24:17 -0000 On 08/11/2005, at 10:16, Alexander Leidinger wrote: > Ion-Mihai Tetcu wrote: > >> On Mon, 07 Nov 2005 14:56:45 +0100 >> Alexander Leidinger wrote: >> >>> Ion-Mihai Tetcu wrote: >>> >>> > On Mon, 07 Nov 2005 11:18:00 +0100 >>> > Alexander Leidinger wrote: >>> > >>> >> > - and performaces is a nightmare on atapi harddisks >>> >> >>> >> AFAIR 4.x enables the write cache (bad if there's a power failure >>> >> in the soft-updates case, since without native command =20 >>> queueing the >>> >> drivers may reorder writes witout the possibility to notify >>> >> soft-updates about it), > > I' a little bit confused now. The man page says the WC is enabled =20 > by default, > but I was under the impression, that it is disabled by default (I =20 > remember > there was a discussion about this long ago). On my systems it is =20 > disabled, > since I haven't removed the loader.conf line since the 4.x days. =20 > S=F8ren, is > this a bug in the man page or did I got it wrong? WC is enabled by default on modern FreeBSD's, it was tried to disable =20= it once but the performance hit quickly changed that decision. >>> > So on NCQ disks write_caching should be safe from consistency >>> > point-of-view ? >>> >>> AFAIK: Enabling the write cache doesn't mean you use NCQ. So just >>> because your drive is able to do NCQ, you shouldn't enable the write >>> cache. If your controller, your disk and the OS is able to use NCQ, >>> and you enable the use of NCQ, then everything is fine... assuming >>> the drive doesn't lie to you. AFAIR there are or there where some >>> drives which lie(d), but I don't remember the details. >> >> And finding out the what disk and controller use NCQ _and_ are >> supported by our drivers can be done how ? > > Asking sos@FreeBSD.org (CCed) would be a way to find it out... NCQ is not supported on FreeBSD at this time, support is in the works =20= and will get into -current once its far enough along. Note that TCQ =20 is only supported (and buggy since the PAE code was added) in 4.x. > At first I thought atacontrol tells you about it. But the =20 > "atacontrol cap > ad0" command just tells you about the capabilities of the drive, =20 > not which > of those capabilities are used by the driver (would be nice to have, > specially in the light of seeing TCQ enabled but knowing that you =20 > said is > doesn't work... at least with the previous implementation of ata). > > S=F8ren, is there a way to en-/disable some of the capabilities with =20= > atacontrol > or something else? Not as is, but it could be added along the way. However some of the =20 capabilties depends on both disk and controller and in most cases =20 also the OS have support for it. Furthermore some if the capabilities =20= only makes sense to change during boot. S=F8ren Schmidt sos@FreeBSD.org