From owner-freebsd-hackers Mon May 5 14:08:04 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id OAA20330 for hackers-outgoing; Mon, 5 May 1997 14:08:04 -0700 (PDT) Received: from iworks.InterWorks.org (deischen@iworks.interworks.org [128.255.18.10]) by hub.freebsd.org (8.8.5/8.8.5) with ESMTP id OAA20291; Mon, 5 May 1997 14:08:00 -0700 (PDT) Received: (from deischen@localhost) by iworks.InterWorks.org (8.7.5/) id QAA06100; Mon, 5 May 1997 16:09:13 -0500 (CDT) Message-Id: <199705052109.QAA06100@iworks.InterWorks.org> Date: Mon, 5 May 1997 16:09:13 -0500 (CDT) From: "Daniel M. Eischen" To: RGireyev@bellind.com, owner-freebsd-hackers@FreeBSD.ORG Subject: Re: Subject: SMP hardware recommendations Cc: hackers@FreeBSD.ORG Sender: owner-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk > > I'd like to comment about the SCSI controller(s) > > If the memory in my empty head serves me right. > > I believe the desired config is NOT an UltraWide > > with a huge (9G) disk hanging off it, but rather > > a couple of cheaper controllers with smaller > > drives (no bigger than 4G) and for optimum > > performance 2G. For more info try to search for > > Joe Grecos comments in the -hackers archive in the > > search engine. Andrew I know you've seen them though. [...] > If you want multiple controllers, knock yourself out. 3 PCI slots to > play with, and 2940's are way way down in price. 1 ISA slot on board. I wouldn't recommend buying the 2940U for disk intensive operations. As noted before, this puppy only has 3 SCBs as compared to 16 SCBs on the 2940UW/3940UW. Even if you don't use the wide cable, the 13 extra commands will be worth it. The ahc driver also supports SCB paging (paging in and out of kernel memory) to allow for more SCBs, but there is overhead in that too.  Dan Eischen deischen@iworks.InterWorks.org