From owner-freebsd-usb@FreeBSD.ORG Fri Jan 28 08:48:25 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 A51C6106564A for ; Fri, 28 Jan 2011 08:48:25 +0000 (UTC) (envelope-from hselasky@c2i.net) Received: from swip.net (mailfe03.c2i.net [212.247.154.66]) by mx1.freebsd.org (Postfix) with ESMTP id 2F7148FC16 for ; Fri, 28 Jan 2011 08:48:24 +0000 (UTC) X-Cloudmark-Score: 0.000000 [] X-Cloudmark-Analysis: v=1.1 cv=0KkIQGagYCvnrzE3Z2Lmid87OPdbX6VLcZYwAuLMZ50= c=1 sm=1 a=-lJg8f7At1MA:10 a=8nJEP1OIZ-IA:10 a=CL8lFSKtTFcA:10 a=i9M/sDlu2rpZ9XS819oYzg==:17 a=s6gVvOvmmxDJEFLdTWcA:9 a=Gfqfe-kOo8U0TP3AT5lX2-YEsVYA:4 a=wPNLvfGTeEIA:10 a=i9M/sDlu2rpZ9XS819oYzg==:117 Received: from [188.126.198.129] (account mc467741@c2i.net HELO laptop002.hselasky.homeunix.org) by mailfe03.swip.net (CommuniGate Pro SMTP 5.2.19) with ESMTPA id 80219148; Fri, 28 Jan 2011 09:48:23 +0100 From: Hans Petter Selasky To: "Daniel O'Connor" Date: Fri, 28 Jan 2011 09:48:27 +0100 User-Agent: KMail/1.13.5 (FreeBSD/8.2-PRERELEASE; KDE/4.4.5; amd64; ; ) References: <9CF6C32F-E230-446B-94FC-C57F0F02B0E4@gsoft.com.au> <201101280858.05077.hselasky@c2i.net> <2E5206C4-9327-4270-8948-FD44C62C645D@gsoft.com.au> In-Reply-To: <2E5206C4-9327-4270-8948-FD44C62C645D@gsoft.com.au> X-Face: *nPdTl_}RuAI6^PVpA02T?$%Xa^>@hE0uyUIoiha$pC:9TVgl.Oq, NwSZ4V"|LR.+tj}g5 %V,x^qOs~mnU3]Gn; cQLv&.N>TrxmSFf+p6(30a/{)KUU!s}w\IhQBj}[g}bj0I3^glmC( :AuzV9:.hESm-x4h240C`9=w MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201101280948.27511.hselasky@c2i.net> 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, 28 Jan 2011 08:48:25 -0000 On Friday 28 January 2011 09:42:57 Daniel O'Connor wrote: > On 28/01/2011, at 18:28, Hans Petter Selasky wrote: > > For this kind of applications ISOCHRONOUS transfers should be used. Then > > you can have a double buffer guard in the range 1-56ms, regardless of > > the buffer size the hardware uses. > > Hmm, OK, I will have a look at changing it, although it is a bit of a pain > because you can't stall an ISO EP and I'm using stall to indicate an > error. Hi, There are some hard limits in the libusb source code. Just search for 16K in decimal. In the kernel the limit is bigger and I guess you don't need to change anything there. > Is it possible to change the amount that is buffered? This is a specialised > application so a custom kernel is no problem. Even a hint in the right > direction would be greatly appreciated :) > > > You could also try an XHCI controller, because the BULK buffering is done > > differently there. > > OK thanks, I'll try that too. --HPS