From owner-freebsd-hackers Mon Nov 11 15:45:47 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id PAA21704 for hackers-outgoing; Mon, 11 Nov 1996 15:45:47 -0800 (PST) Received: from Kitten.mcs.com (Kitten.mcs.com [192.160.127.90]) by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id PAA21697 for ; Mon, 11 Nov 1996 15:45:43 -0800 (PST) Received: from Mailbox.mcs.com (Mailbox.mcs.com [192.160.127.87]) by Kitten.mcs.com (8.8.2/8.8.2) with ESMTP id RAA21351; Mon, 11 Nov 1996 17:45:21 -0600 (CST) Received: from Jupiter.Mcs.Net (karl@Jupiter.mcs.net [192.160.127.88]) by Mailbox.mcs.com (8.8.2/8.8.2) with ESMTP id RAA25570; Mon, 11 Nov 1996 17:45:20 -0600 (CST) Received: (from karl@localhost) by Jupiter.Mcs.Net (8.8.2/8.8.2) id RAA10212; Mon, 11 Nov 1996 17:45:18 -0600 (CST) From: Karl Denninger Message-Id: <199611112345.RAA10212@Jupiter.Mcs.Net> Subject: Re: Problems restoring Backups !!! To: gibbs@freefall.freebsd.org (Justin T. Gibbs) Date: Mon, 11 Nov 1996 17:45:17 -0600 (CST) Cc: andreas@klemm.gtn.com, acorreia@marlin.com.br, hackers@freebsd.org In-Reply-To: <199611112303.PAA17972@freefall.freebsd.org> from "Justin T. Gibbs" at Nov 11, 96 03:03:09 pm X-Mailer: ELM [version 2.4 PL24] Content-Type: text Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > > >options AHC_SCBPAGING_ENABLE > >options AHC_TAGENABLE # still makes problems with tap > >es > >options SCSI_REPORT_GEOMETRY > > > >I get now thousands of (looping) Queue Full lines, when trying to make > >a backup using dump(8). > > Remove the printf and see if it works okay for you. The printf probably > causes a cascade effect since it will cause syslogd to write to the disk. > I'll also look into changing the code to try to actively reduce the number > of transactions allowed to the target, but to do that correctly is a lot of > work - which is the main reason I added it to the generic SCSI layer on the > SCSI branch. Where can I find documentation on those AHC_* options, what they do, what they might break, and when (or if) I should enable them? My problem with turning them on is that I've heard that some older disks puke badly with them enabled. On the other hand, I presume there are *serious* performance enhancements available with them, specifically tagged-queueing. On our news server systems, I bet we could use that. But if its going to be something that comes at the risk of data corruption I'm leaving it off! -- -- Karl Denninger (karl@MCS.Net)| MCSNet - The Finest Internet Connectivity http://www.mcs.net/~karl | T1's from $600 monthly to FULL DS-3 Service | 32 Analog Prefixes, 13 ISDN, Web servers $75/mo Voice: [+1 312 803-MCS1 x219]| Email to "info@mcs.net" WWW: http://www.mcs.net/ Fax: [+1 312 248-9865] | 2 FULL DS-3 Internet links; 400Mbps B/W Internal