From owner-freebsd-usb@FreeBSD.ORG Fri Feb 18 14:40:24 2011 Return-Path: Delivered-To: freebsd-usb@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A1024106564A for ; Fri, 18 Feb 2011 14:40:24 +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 20A7D8FC18 for ; Fri, 18 Feb 2011 14:40:23 +0000 (UTC) Received: from ur.dons.net.au (ppp203-122-198-244.lns6.adl6.internode.on.net [203.122.198.244]) (authenticated bits=0) by cain.gsoft.com.au (8.14.4/8.14.3) with ESMTP id p1IEe77r023111 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Sat, 19 Feb 2011 01:10:08 +1030 (CST) (envelope-from doconnor@gsoft.com.au) Mime-Version: 1.0 (Apple Message framework v1082) Content-Type: text/plain; charset=us-ascii From: "Daniel O'Connor" In-Reply-To: <0F80A010-B97C-4D05-B604-5EF4B07EF248@gsoft.com.au> Date: Sat, 19 Feb 2011 01:10:07 +1030 Content-Transfer-Encoding: quoted-printable Message-Id: References: <9CF6C32F-E230-446B-94FC-C57F0F02B0E4@gsoft.com.au> <201101221433.23194.hselasky@c2i.net> <6AD22899-0B00-483D-A01E-786029A82C9F@gsoft.com.au> <201101280858.05077.hselasky@c2i.net> <0F80A010-B97C-4D05-B604-5EF4B07EF248@gsoft.com.au> To: "Daniel O'Connor" X-Mailer: Apple Mail (2.1082) X-Spam-Score: 0.163 () BAYES_00,RDNS_DYNAMIC X-Scanned-By: MIMEDefang 2.67 on 203.31.81.10 Cc: freebsd-usb@freebsd.org Subject: Re: libusb performance on 8.1 X-BeenThere: freebsd-usb@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: FreeBSD support for USB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 18 Feb 2011 14:40:24 -0000 On 03/02/2011, at 17:26, Daniel O'Connor wrote: > BTW do you have a feel for the latency in bulk vs iso? I currently = have 5-10 msec of buffering in the hardware which I plan on increasing = but I'm not sure what a reasonable amount would be :) I increased this by a factor of 8 but I still get drop outs during disk = activity. I timed libusb_handle_events_timeout() with a timeout of 1 millisecond = and it quite often exceeds this (by a significant amount) eg.. Triggered at 1298039742 2011/02/18 14:35:27:ugsio_child: libusb took > 10msec - 32.44 ms 2011/02/18 14:35:27:ugsio_child: libusb took > 10msec - 27.19 ms 2011/02/18 14:35:27:ugsio_child: libusb took > 10msec - 25.27 ms 2011/02/18 14:35:27:ugsio_child: libusb took > 10msec - 21.83 ms 2011/02/18 14:35:36:ugsio_child: libusb took > 10msec - 48.23 ms Error during acquisition - ERROR:305 UGSIO aborted transfer: stalled (still using bulk transfers for now) -- 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