From owner-freebsd-hackers Wed Jan 1 19:26:01 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.4/8.8.4) id TAA12441 for hackers-outgoing; Wed, 1 Jan 1997 19:26:01 -0800 (PST) Received: from news1.gtn.com (news1.gtn.com [192.109.159.3]) by freefall.freebsd.org (8.8.4/8.8.4) with ESMTP id TAA12436 for ; Wed, 1 Jan 1997 19:25:58 -0800 (PST) Received: (from uucp@localhost) by news1.gtn.com (8.7.2/8.7.2) with UUCP id EAA29709; Thu, 2 Jan 1997 04:16:18 +0100 (MET) Received: (from andreas@localhost) by klemm.gtn.com (8.8.4/8.8.2) id EAA09688; Thu, 2 Jan 1997 04:06:36 +0100 (MET) Message-ID: Date: Thu, 2 Jan 1997 04:06:36 +0100 From: andreas@klemm.gtn.com (Andreas Klemm) To: jfieber@indiana.edu (John Fieber) Cc: hackers@FreeBSD.org Subject: Re: New motherboard breaks tape drive References: X-Mailer: Mutt 0.55-PL15 Mime-Version: 1.0 In-Reply-To: ; from "John Fieber" on Jan 1, 1997 19:07:01 -0500 Sender: owner-hackers@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk > > How is your kernel config file. What's the SC200 ? > > PCI controller ? AHA 2940 compatible or what ? > NCR. See kernel config below. I think it's a PCI controller ?! I don't know the NCR ones well... > > BTW, did you try team from the ports collection ? > Yes, and it doesn't offer any improvement over dump/tar/dd with > sufficiently large block sizes. Then it must be something other I think... > options BOUNCE_BUFFERS #include support for DMA bounce buffers You only need this option when using SCSI DMA controllers like the AHA 1542B, which only could address 16 MB address space and only in the case when having more than 16MB of system memory. It might be the case, that this bounce buffering brings your system's performance down. Another good idea would be, to create a very small kernel without many kernel options like DEVFS and other options... Strip down GENERIC, since it has less "esoteric" options in it and reduce it to the drivers you really need... This might also help tracking down the "bug" ... But I think BOUNCE_BUFFERS might be the real culprit... Andreas /// -- andreas@klemm.gtn.com /\/\___ Wiechers & Partner Datentechnik GmbH Andreas Klemm ___/\/\/ Support Unix -- andreas.klemm@wup.de pgp p-key http://www-swiss.ai.mit.edu/~bal/pks-toplev.html >>> powered by <<< ftp://sunsite.unc.edu/pub/Linux/system/Printing/aps-491.tgz >>> FreeBSD <<<