From owner-freebsd-hackers@FreeBSD.ORG Thu Dec 27 23:11:47 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 3F36FDDA for ; Thu, 27 Dec 2012 23:11:47 +0000 (UTC) (envelope-from doconnor@gsoft.com.au) Received: from cain.gsoft.com.au (cain.gsoft.com.au [203.31.81.10]) by mx1.freebsd.org (Postfix) with ESMTP id 375638FC0C for ; Thu, 27 Dec 2012 23:11:44 +0000 (UTC) Received: from ur.dons.net.au (ppp14-2-18-58.lns21.adl2.internode.on.net [14.2.18.58]) (authenticated bits=0) by cain.gsoft.com.au (8.14.4/8.14.3) with ESMTP id qBRMtk0Z051402 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Fri, 28 Dec 2012 09:25:51 +1030 (CST) (envelope-from doconnor@gsoft.com.au) Subject: Re: FreeBSD for serious performance? Mime-Version: 1.0 (Mac OS X Mail 6.2 \(1499\)) Content-Type: multipart/signed; boundary="Apple-Mail=_6E156F4A-83B7-487B-B28B-D16BCF726430"; protocol="application/pkcs7-signature"; micalg=sha1 From: "Daniel O'Connor" In-Reply-To: <20121227031430.GD82100@server.rulingia.com> Date: Fri, 28 Dec 2012 09:25:45 +1030 Message-Id: <66E63A5B-FD16-4B1C-94D3-EA15F51EC22F@gsoft.com.au> References: <20121226084805.91840@gmx.com> <20121227031430.GD82100@server.rulingia.com> To: Peter Jeremy X-Mailer: Apple Mail (2.1499) X-Spam-Score: 0.163 () BAYES_00,RDNS_DYNAMIC X-Scanned-By: MIMEDefang 2.67 on 203.31.81.10 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: freebsd-hackers@freebsd.org, Dieter BSD X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 27 Dec 2012 23:11:47 -0000 --Apple-Mail=_6E156F4A-83B7-487B-B28B-D16BCF726430 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii On 27/12/2012, at 13:44, Peter Jeremy wrote: >> I've only caught it hanging forever once. It only takes a few >> milliseconds to cause incoming data to be lost, >=20 > I'm not sure what you mean by this. FreeBSD is not a real-time > operating system and so offers no guarantees on how long it will > take before incoming data will be processed. If you have an > application that relies on incoming data being processed within > milliseconds, you may need to do some redesign. In practise FreeBSD can actually do this (at least for moderate IO = loads). At $work we use a USB interface to acquire ~10MB/sec from a data = acquisition system which has a 96k FIFO (which is ~10 msec of = buffering). We use 3ware RAID cards to write to disk on Supermicro boards though, = you get what you pay for.. -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C --Apple-Mail=_6E156F4A-83B7-487B-B28B-D16BCF726430--