From owner-freebsd-hardware Thu Feb 20 16:41:48 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id QAA20159 for hardware-outgoing; Thu, 20 Feb 1997 16:41:48 -0800 (PST) Received: from nexgen.ampr.org (max20-105.HiWAAY.net [208.147.153.105]) by freefall.freebsd.org (8.8.5/8.8.5) with ESMTP id QAA20154 for ; Thu, 20 Feb 1997 16:41:39 -0800 (PST) Received: from nexgen (localhost [127.0.0.1]) by nexgen.ampr.org (8.8.5/8.8.4) with ESMTP id SAA28380; Thu, 20 Feb 1997 18:40:54 -0600 (CST) Message-Id: <199702210040.SAA28380@nexgen.ampr.org> X-Mailer: exmh version 1.6.9 8/22/96 To: Bruce Evans cc: hardware@FreeBSD.org From: dkelly@hiwaay.net Subject: Re: _big_ IDE disks? In-reply-to: Message from Bruce Evans of "Thu, 20 Feb 1997 15:37:15 +1100." <199702200437.PAA19813@godzilla.zeta.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Thu, 20 Feb 1997 18:40:51 -0600 Sender: owner-hardware@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk Bruce Evans writes: > > Run `dd if=/dev/zero of=/dev/null bs=1m count=1000' and complain if > the throughtput is much lower than 120MB/sec. nexgen: {366} uname -a FreeBSD nexgen 2.2-GAMMA FreeBSD 2.2-GAMMA #0: Sat Feb 8 07:30:46 CST 1997 dkelly@nexgen.ampr.org:/usr/src/sys/compile/NEXGEN i386 nexgen: {367} dd if=/dev/zero of=/dev/null bs=1m count=1000 1000+0 records in 1000+0 records out 1048576000 bytes transferred in 30.300733 secs (34605631 bytes/sec) System is a "P90" NexGen Nx586, PCI. CPU ID's as a 386, and thats the way my kernel is compiled. Who do I complain to? :-) OTOH, it does "make world" in just over 7 hours with its 64 bit wide bus. About the same as my super cheap AMD 5x86/133-P75 on a 32 bit wide bus. Maybe I'm in the market for a new CPU/MB. What gives 120MB/sec performance? This is the $116 5x86/133 w/ 256k of write-thru cache: PeeCee: {1001} dd if=/dev/zero of=/dev/null bs=1m count=1000 1000+0 records in 1000+0 records out 1048576000 bytes transferred in 24.782880 secs (42310498 bytes/sec) PeeCee: {1002} uname -a FreeBSD PeeCee.tbe.com 3.0-CURRENT FreeBSD 3.0-CURRENT #0: Wed Feb 5 13:06:39 CST 1997 dkelly@PeeCee.tbe.com:/usr/src/sys/compile/PEECEE i386 PeeCee would probably beat NexGen in "make world" if I'd replace PeeCee's mode 0 IDE HD with NexGen's 2G narrow Barracuda. mdsc1 102% hinv 1 100 MHZ IP20 Processor FPU: MIPS R4000 Floating Point Coprocessor Revision: 0.0 CPU: MIPS R4000 Processor Chip Revision: 2.2 Hmdsc1 103% time dd if=/dev/zero of=/dev/null bs=1000k count=1000 1000+0 records in 1000+0 records out 0.0u 9.9s 0:10 97% 0+0k 0+0io 0pf+0w mdsc1 104% expr 1048576000 / 10 104857600 Doggnone! Can't even get 120MB/sec out of a moderately old SGI Indigo! But much closer. Hey, this was sorta fun. Time to dig out the 486dx33 and 386sx16. :-) -- David Kelly N4HHE, dkelly@hiwaay.net ===================================================================== The human mind ordinarily operates at only ten percent of its capacity -- the rest is overhead for the operating system.