From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Date: Tue, 15 Feb 2005 23:10:49 +0000 Subject: Re: [UDEV, PATCH] Add profiling support to Makefile Message-Id: <20050215231049.GB16991@kroah.com> List-Id: References: <200502131716.55756.mbuesch@freenet.de> In-Reply-To: <200502131716.55756.mbuesch@freenet.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-hotplug@vger.kernel.org On Tue, Feb 15, 2005 at 10:12:56AM +0100, Kay Sievers wrote: > On Tue, 2005-02-15 at 09:45 +0100, Michael Buesch wrote: > >Quoting Greg KH : > >> On Sun, Feb 13, 2005 at 05:16:51PM +0100, Michael Buesch wrote: > >> > Hi, > >> > > >> > This patch adds an option to the Makefile to enable > >> > profiling. Profiling is only enabled, when not building > >> > against klibc, as klibc lacks support for mcount(). > >> > > >> > Please apply. Thanks. > >> > >> You forgot to update the documentation about this option, so I'll hold > >> off till you redo that :) > > > >Oops. :O Here it is. > > > >> Also, what has profiling information helped you out with in udev? Found > >> anything interesting? Or are you just using it for coverage analysis > >> (which is a flawed thing, but that's another topic...) > > > >I did not do much testing, yet, because of missing time. > >But I will do that. > >My first testrun showed that the namedev matchrule function and the udevdb > >are the slowest parts of the whole executable. So maybe there's some > >optimization possible. But I'll look closer at it later. > > The biggest part of it seems libsysfs. A replacement of the attribute > reading functions with a simple open() gives ~20% speed increase for > udevstart on my box. As I doubt libsysfs will be fixed in this regard anytime soon, want to add this to the tree? A 20% speed increase for such a simple change is a very good thing to have :) thanks, greg k-h ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_ide95&alloc_id396&op=click _______________________________________________ Linux-hotplug-devel mailing list http://linux-hotplug.sourceforge.net Linux-hotplug-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel