Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756887Ab2FTPsu (ORCPT ); Wed, 20 Jun 2012 11:48:50 -0400 Received: from isilmar-3.linta.de ([188.40.101.200]:49530 "EHLO linta.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753883Ab2FTPst (ORCPT ); Wed, 20 Jun 2012 11:48:49 -0400 Date: Wed, 20 Jun 2012 17:48:42 +0200 From: Dominik Brodowski To: daniel.vetter@ffwll.ch, dri-devel@lists.freedesktop.org, gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org Subject: Thunderbolt, Apple Monitor & MBA, and excess kworker load Message-ID: <20120620154842.GA5788@air.dominikbrodowski.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 935 Lines: 22 Hi, At work, I wish to attach a 27" Apple Display using thunderbolt to my Mac Book Air 4,2 13". Using OS X, it works fine, but as I prefer using Linux, I tested out Ubuntu's stock kernel and (among other) 3.5.0-rc3+ as of f40759e. Hotplug doesn't work (known issue), but also with coldplug the display reacts _very_ slow, way too slow for real use: The screen updates only every half second or so. Is this a known bug? Might something go afoul with kworker -- they need about 75% of the CPU with the large display attached, and less than 1% _without_ the large display. Any hints are most welcome, also on where I may dig further to determine the root causes... Thanks & best, Dominik -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/