From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:49784 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933767Ab0FCDlF (ORCPT ); Wed, 2 Jun 2010 23:41:05 -0400 Message-ID: <4C072451.7090001@infradead.org> Date: Thu, 03 Jun 2010 00:41:05 -0300 From: Mauro Carvalho Chehab MIME-Version: 1.0 To: Andrew Morton CC: "Rafael J. Wysocki" , Maciej Rutecki , linux-media@vger.kernel.org Subject: Re: [Bugme-new] [Bug 16077] New: Drop is video frame rate in kernel .34 References: <20100602140916.759d7159.akpm@linux-foundation.org> In-Reply-To: <20100602140916.759d7159.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em 02-06-2010 18:09, Andrew Morton escreveu: > On Sun, 30 May 2010 14:29:55 GMT > bugzilla-daemon@bugzilla.kernel.org wrote: > >> https://bugzilla.kernel.org/show_bug.cgi?id=16077 > > 2.6.33 -> 2.6.34 performance regression in dvb webcam frame rates. I don't think this is a regression. Probably, the new code is allowing a higher resolution. As the maximum bandwidth from the sensor to the USB bridge doesn't change, and a change from QVGA to VGA implies on 4x more pixels per frame, as consequence, the number of frames per second will likely reduce by a factor of 4x. I've asked the reporter to confirm what resolutions he is setting on 2.6.33 and on 2.6.34, just to double check if my thesis is correct. Cheers, Mauro.