From owner-freebsd-questions Mon May 15 11:59:21 2000 Delivered-To: freebsd-questions@freebsd.org Received: from mass.cdrom.com (adsl-63-202-176-114.dsl.snfc21.pacbell.net [63.202.176.114]) by hub.freebsd.org (Postfix) with ESMTP id 190EE37B89D for ; Mon, 15 May 2000 11:59:14 -0700 (PDT) (envelope-from msmith@mass.cdrom.com) Received: from mass.cdrom.com (localhost [127.0.0.1]) by mass.cdrom.com (8.9.3/8.9.3) with ESMTP id LAA13224; Mon, 15 May 2000 11:59:28 -0700 (PDT) (envelope-from msmith@mass.cdrom.com) Message-Id: <200005151859.LAA13224@mass.cdrom.com> X-Mailer: exmh version 2.1.1 10/15/1999 To: "Simon Clayton" Cc: "Mitch Vincent" , "Chris Phillips" , freebsd-questions@freebsd.org Subject: Re: FreeBSD SMP In-reply-to: Your message of "Sat, 13 May 2000 14:18:37 BST." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 15 May 2000 11:59:28 -0700 From: Mike Smith Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > Mike, > > You said > > Buy something smaller. Benchmark your application, and determine what > your performance requirements are. Make appropriate purchasing > decisions > based on quantifiable results. > > Can you give me any pointers on how to go about this. Gack. This is the sort of thing you should be learning *before* you take on an exercise like this. No offense meant, but it's kinda like buying an SUV to move your poodle around. You measure the dog before you buy the vehicle... At any rate, you should start by familiarising yourself with some of the basic system monitoring tools; top and systat are the most useful. The output of 'systat -vmstat' is extremely useful in determining where the system is spending it's time, and which resources are being under/over utilised. > I have a web site that we are currently building using > FreeBSD4.0/Apache1.3.12/PHP3.0.16/MySQL3.22.32 > and have some very large database tables/joins etc. At the moment we > just use > the very very sophisticated tuning method of "allocating bigger buffers > until it > runs faster" and any information on a more scientific approach would be > greatly > appreciated. Load the site up a little and look at some of the abovementioned data; see who is using what (eg. look at top output) etc. With mysql, you'll typically only have one process doing anything meaningful to the database at a given time - for something like this, you may be better off with a high-powered uniprocessor machine (eg. 1GHz Athlon) than an SMP box. If you're heavily I/O bound, you may need to look at your I/O subsystem. If you have swarms of small processes nickle-and-diming the system to death, SMP may help. If you're swapping, you will need more RAM. Sorry for the vehemence in the original reply - watching this process is somewhat akin to being a grizzled mechanic listening to the pimply teenager behind the Jiffy Lube counter explaining how putting more stickers on your car will improve your gas mileage. -- \\ Give a man a fish, and you feed him for a day. \\ Mike Smith \\ Tell him he should learn how to fish himself, \\ msmith@freebsd.org \\ and he'll hate you for a lifetime. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message