From owner-freebsd-hackers Tue Jul 9 17:57:20 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 323ED37B400 for ; Tue, 9 Jul 2002 17:57:17 -0700 (PDT) Received: from april.chuckr.org (april.chuckr.org [66.92.147.143]) by mx1.FreeBSD.org (Postfix) with ESMTP id 22CD443E3B for ; Tue, 9 Jul 2002 17:57:16 -0700 (PDT) (envelope-from chuckr@chuckr.org) Received: from localhost (chuckr@localhost) by april.chuckr.org (8.11.6/8.11.3) with ESMTP id g6A0ugq31744; Tue, 9 Jul 2002 20:56:42 -0400 (EDT) (envelope-from chuckr@chuckr.org) Date: Tue, 9 Jul 2002 20:56:41 -0400 (EDT) From: Chuck Robey To: Don Lewis Cc: , , , Subject: Re: offtopic: low level format of IDE drive. In-Reply-To: <200207091029.g69ATLwr003533@gw.catspoiler.org> Message-ID: <20020709205446.E945-100000@april.chuckr.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Tue, 9 Jul 2002, Don Lewis wrote: > On 8 Jul, Peter Wemm wrote: > > Julian Elischer wrote: > >> this is not a 'reformat' > >> > >> what I want to do is an old-fashionned refomat/verify where the controller > >> writes new track headers etc. > > > > The thing is, just about all IDE drives more than a few GB or so do 'track > > writing' and have no fixed sectoring or sector positioning. ie: each time > > you write a single sector to a track, it does a read-modify-write of *THE > > ENTIRE TRACK*. This is why we have to have write caching turned on for IDE > > drives to get decent performance. Without it, it essentially rewrites the > > entire track over and over and over again because it cannot fill its write > > buffer in order to write a contiguous block to completely replace what was > > there before. ie: each track is one giant physical sector with multiple logical > > sectors inside it. > > > > The really annoying thing is that most newer scsi drives do this too. > > How readily available is the information about which drives do this? As > someone who only buys the occasional drive, I'd rather not have to buy > one and do the evaluation myself using the method mentioned later in > this thread. > > > > Get a UPS if you value the data. :-] > > That doesn't help if the cat knocks a book off the shelf onto the power > switch, or if you trip over the cord between the UPS and the computer, > or if the magic smoke escapes from the computer power supply. I've seen some BIOSes that allowed you to force the low-level format. Alternatively, you could run an old copy of dos that had "debug" on it and tell it to "g c800:0" which was the address of the disk ROM routine; it worked very reliably for me (before I learned about scsi disks!) > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-hackers" in the body of the message > ---------------------------------------------------------------------------- Chuck Robey | Interests include C & Java programming, FreeBSD, chuckr@chuckr.org | electronics, communications, and signal processing. New Year's Resolution: I will not sphroxify gullible people into looking up fictitious words in the dictionary. ---------------------------------------------------------------------------- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message