Date: Wed, 14 Apr 1999 11:58:39 +0930 From: Greg Lehey <grog@lemis.com> To: dan@wolf.com, freebsd-questions@FreeBSD.ORG Subject: High "intr" rates (was: Help understanding output from systat) Message-ID: <19990414115839.B81628@lemis.com> In-Reply-To: <19990413093523.A24567@ns.wolf.com>; from dan@wolf.com on Tue, Apr 13, 1999 at 09:35:23AM -0700 References: <19990413093523.A24567@ns.wolf.com>
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On Tuesday, 13 April 1999 at 9:35:23 -0700, dan@wolf.com wrote: > Greetings, all. I'm hoping someone can help me > make sense of the output from "systat -v" on my > machine. I'm running FreeBSD 2.2.8 on a Celeron > 333A (with L2 cache), 256 MB RAM, 8 GB IDE drive > (soon to be replaced with Ultra-SCSI), and a 4 > GB Ultra-SCSI drive on an Adaptec 2940UW. > > I started examing systat to try and dtermine why > my overall throughput is so low - I'm currently > maxing out at around 2 Mbits on a 10 Mbit circuit. > Running "systat -v" shows my CPU usage to be sitting > right around 13% Sys, 32% Intr, 9% User. That Intr > percentage seems might god-awful high. Am I correct > in assuming that something is badly amiss here? It suggests to me that you're doing a lot of disk I/O. 2.x doesn't support DMA on IDE drives. You'll find that 3.x in conjunction with DMA will give you a great performance increase. Interrupt time, more than anything else, gives you the feeling that the computer is sluggish, and the difference with DMA is very noticeable. Greg -- When replying to this message, please copy the original recipients. For more information, see http://www.lemis.com/questions.html See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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