From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 17 May 2001 21:30:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 17 May 2001 21:30:31 -0400 Received: from felix.convergence.de ([212.84.236.131]:6057 "EHLO convergence.de") by vger.kernel.org with ESMTP id ; Thu, 17 May 2001 21:30:28 -0400 Date: Fri, 18 May 2001 03:29:23 +0200 From: Felix von Leitner To: linux-kernel@vger.kernel.org Subject: problem: reading from (rivafb) framebuffer is really slow Message-ID: <20010518032923.A17686@convergence.de> Mail-Followup-To: linux-kernel@vger.kernel.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.16i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org When benchmarking DirectFB, I found that a typical software alpha blending rectangle fill is completely dominated (I'm talking 90% of the CPU cycles here) by the time it takes to read pixels from the framebuffer. The pixels are read linearly in chunks of aligned 32-bit words. It's a Geforce 2 GTS in 1024x768 with 32-bit color depth using rivafb. This looks quite crass to me. Any ideas? Maybe rivafb does not initialize AGP and the card is in PCI mode or something? Felix