From owner-freebsd-smp Mon Nov 10 10:01:55 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id KAA15867 for smp-outgoing; Mon, 10 Nov 1997 10:01:55 -0800 (PST) (envelope-from owner-freebsd-smp) Received: from george.arc.nasa.gov (george.arc.nasa.gov [128.102.194.142]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id KAA15862 for ; Mon, 10 Nov 1997 10:01:53 -0800 (PST) (envelope-from lamaster@george.arc.nasa.gov) From: lamaster@george.arc.nasa.gov Received: (from lamaster@localhost) by george.arc.nasa.gov (8.8.7/8.8.7) id JAA06997 for freebsd-smp@FreeBSD.ORG; Mon, 10 Nov 1997 09:59:41 -0800 (PST) Date: Mon, 10 Nov 1997 09:59:41 -0800 (PST) Message-Id: <199711101759.JAA06997@george.arc.nasa.gov> To: freebsd-smp@freebsd.org Subject: Re: Best processor? Sender: owner-freebsd-smp@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > We went from a Pentium Pro/200 w/512k to a Pentium II/266 and it > significantly faster (uniprocessor). (Before LX chipset was out) : > The L2 cache is slower, which may cause problems. But the processors : > Slot 2 (II?) will have a full-speed L2 Cache and support 4-way smp. > It will be targeted at server-only marker. So far, I have not seen any numbers for the definitive benchmark: "make world". For the numbers to be meaningful, we need to define the conditions. *********************** converge on benchmark standard ******************* PPro or PII@nMHz, 1 or 2 processors, at least 64 MB EDO DRAM Orion (anybody using Orion?), Natoma, or LX (most common disk controller here: Symbios 3C875-Ultra-wide-based ????) (kernel configured with SCSI controller tagged queueing on) (most common disks here: Quantum Atlas II Ultra-Wide ???) /usr/src mounted: normally /usr/obj mounted: async,noatime (What "world" we are making: I assume 3.0-current) /etc/make.conf: CFLAGS= -O -pipe make -j4 -DNOCLEANDIR world ********************** any comments or corrections? ********************** Once we get the numbers for the make world benchmark in a standard configuration, we will know which processor is really, truly faster. ;-) BTW, most of the numbers I have seen have made it pretty much a wash, that is, at the same clock, PPro and PII seem to be about the same performance. On the PPro, an L1 cache miss is handled faster, but, on a PII, you have a bigger L1 cache. And the basic CPU cores are apparently nearly identical. One thing I am not clear on is the SMP performance. The PPro was notoriously slow at main-memory writes because of the cache-coherence protocol. I'm not sure if a PII on LX might be faster? If so, this could be a big advantage for PII/LX on SMP performance. Plus, SDRAM on an LX should help a little, too. So, let's see those benchmark numbers.