From owner-freebsd-questions Wed Jan 22 23: 8:39 2003 Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 237AB37B401 for ; Wed, 22 Jan 2003 23:08:38 -0800 (PST) Received: from rush.telenordia.se (mail.telenordia.se [194.213.64.42]) by mx1.FreeBSD.org (Postfix) with SMTP id 1474043F6D for ; Wed, 22 Jan 2003 23:08:36 -0800 (PST) (envelope-from fuc952d@tninet.se) Received: (qmail 2068 invoked from network); 23 Jan 2003 08:06:10 +0100 Received: from bb-62-5-66-76.bb.tninet.se (62.5.66.76) by mail.telenordia.se with SMTP; 23 Jan 2003 08:06:10 +0100 From: Mark Rowlands Reply-To: fuc952d@tninet.se To: Noah Garrett Wallach Subject: Re: iostat - define Kilobits per transfer Date: Thu, 23 Jan 2003 08:08:33 +0100 User-Agent: KMail/1.5 Cc: freebsd-questions@FreeBSD.ORG References: <20030122191542.J76039@typhoon.enabled.com> <0a8401c2c294$22e6e1e0$0a0aa8c0@dweebsoft.com> <20030122203914.T76039@typhoon.enabled.com> In-Reply-To: <20030122203914.T76039@typhoon.enabled.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200301230808.33307.fuc952d@tninet.se> Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Thursday 23 January 2003 5:40 am, Noah Garrett Wallach wrote: > On Wed, 22 Jan 2003, Dax Eckenberg wrote: > > > so what exactly does KB per transaction mean? what happens if I am > > > handling 300 concurrent users with 160Kbit encoded audio streams - > > > could I in fact do this on this machine? or will I be limited by the > > > 64KB/t issue? > > > > 300 x 160Kbit = approx. 46Mbit/sec. > > A new-ish SCSI drive should be able to easily pump out in excess of 200 > > Mbit/sec. Your bottleneck will be your ethernet adapter long before your > > local storage. Unless your app is designed very poorly. > > okay things are getting clearer over here. what exactly does KB > per transaction mean? I dont understand what this describes? > > - Noah > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message my guess :- iostat -Iw 60 -t da ad0 KB/t Xfrs MB 8.42 71 0.58 so over the period, 71 transfers occurred totalling 0.58MB for an average KB/t of (0.58*1024) / /71 = 8.37 KB/t but maybe the actual avg transfer size is recorded and summarized giving that slight variation?. Try a longer period and see, or read the code...... (the math starts around line 600....) To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message