From owner-freebsd-stable Fri Aug 30 10:43: 8 2002 Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 767AE37B400 for ; Fri, 30 Aug 2002 10:43:04 -0700 (PDT) Received: from kazi.fit.vutbr.cz (kazi.fit.vutbr.cz [147.229.8.12]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1BAF443E42 for ; Fri, 30 Aug 2002 10:43:03 -0700 (PDT) (envelope-from cejkar@fit.vutbr.cz) Received: from kazi.fit.vutbr.cz (localhost [127.0.0.1]) by kazi.fit.vutbr.cz (8.12.5/8.12.5) with ESMTP id g7UHgnls003940 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO); Fri, 30 Aug 2002 19:42:49 +0200 (CEST) Received: (from cejkar@localhost) by kazi.fit.vutbr.cz (8.12.5/8.12.5/Submit) id g7UHgmfr003939; Fri, 30 Aug 2002 19:42:48 +0200 (CEST) X-Authentication-Warning: kazi.fit.vutbr.cz: cejkar set sender to cejkar@fit.vutbr.cz using -f Date: Fri, 30 Aug 2002 19:42:48 +0200 From: Cejka Rudolf To: Matthew Jacob Cc: stable@FreeBSD.ORG Subject: Re: EOT tape handling changed? Message-ID: <20020830174248.GA880@fit.vutbr.cz> References: <20020829100033.GA2174@fit.vutbr.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4i X-Scanned-By: MIMEDefang 2.16 (www . roaringpenguin . com / mimedefang) Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Matthew Jacob wrote (2002/08/29): > I'm not sure what you're talking about here with this test program > (deleted)- unless you've dorked with MAXPHYS defines, the maximum you > can any tape record at is 64K. Ah I see, thank you for very good explanation. Finally I understand, what all changes happened. It would be really good to "copy" EOT handling from Solaris st(7D) page to FreeBSD's sa(4) page. I have tested again my M2 drive with 60 GB native capacity tape and now I understand results reported by my small test program. For my M2 drive, writing speed before logical EOT is about 10 - 15 MB/s, but after LEOT the speed is only about 0.05 MB/s. The capacity after LEOT seems to be around 135 MB (I reset M2 log_sense counters after first returned zero and then readed log_sense hardware compression page after ENOSPC error). > Another issue then arises- should you allow I/O past Early Warning? That's > the whole point of this funky dance. My take is that you *should* allow > I/O (in order to write trailer records, should the application want to). Yes, I agree that we should, but when I saw speed 0.05 MB/s after LEOT, I started to hope that no application wants to use this feature :-) > This is good- send me a separate note about this to remind me, would you? > We *really* need to use hints for this, though. Yes, of course. I have to return soon to tests of 10 new (it seems that) very buggy data cartridges, where SmartClean is often forced many times (I have a record 61 for one full tape pass, where in case of a good cartridge it has to be just 0 or 1), and I will see if timeouts disappeared and then I send something to our vendor and to you too. -- Rudolf Cejka http://www.fit.vutbr.cz/~cejkar Brno University of Technology, Faculty of Information Technology Bozetechova 2, 612 66 Brno, Czech Republic To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message