From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nils Faerber Subject: Re: performance problems? Date: Tue, 19 Nov 2002 15:01:55 +0100 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: <20021119150155.406f1c92.nils@kernelconcepts.de> References: <3DDA3E96.50906@rwth-aachen.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <3DDA3E96.50906-vA1bhqPz9FBZXbeN9DUtxg@public.gmane.org> Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: Thomas List Cc: Acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org On Tue, 19 Nov 2002 14:37:26 +0100 Thomas List wrote: > Hi all, Hello! > I'm working on a small battery applet for my laptop that reads out the > battery status. As I have up to now no better idea I'm pulling the > battery status (/proc/acpi/battery/...) every few seconds (anyone an > idea of how to do this better?). Now a battery applet should consume > as few CPU cycles as possible to not use up the battery itself. So I'm > trying to monitor how much computing time my applet is using. For the > moment I'm doing this using top (I know this is not perfect for that > task ...). Now to the problem: IMHO your assumption are coorect. > After the laptop is running for some time the CPU% value in top is > getting higher and higher. It starts with around 0.3% in the > beginning, after one hour it reaches 1,5% and I had it up to 3% and > more after a longer time. I am quite sure this is not my applet - I > can stop the program and restart it and still get the higher values. I > tried to watch a video in this state and while my program was running > I had short stops in the video play back that match the 2 seconds > interval of pulling the battery status. Without my program running the > stops disappeared. Using a file system copy of /proc/acpi my program > does not show at all on the top list. I cannot explain what you are observing but I can confirm your observations. I see the same "hangs" and CPU usage phenomenon when using a window-maker dock application showing battery information. Everytime the battery is polled by the applet the CPU usage rises and the machine suffers a short hang; approx. 1/4 second. > I am using acpi 20021111 on a 2.4.20-rc1 kernel. The laptop is a Targa > visionary 1600 from actebis (mobile athlon on a Via ProSavage KN133 > "TwisterK" board). I think I did not have such problems with an older > acpi version (20021022 ???) - I will check this out). Same here. Laptop is Asus L3800C. > Now could this be a problem with the acpi implementation or is this > the result of a wrong usage of acpi? I think this is a problem with ACPI... > Btw. - is there any documentation on the /proc/acpi directories > besides Dominik Brodowski's documentation for /proc/acpi/processor? AFAIK not; but would be nice! > Thanks for any help, > Thomas CU nils faerber -- kernel concepts Tel: +49-271-771091-12 Dreisbachstr. 24 Fax: +49-271-771091-19 D-57250 Netphen D1 : +49-170-2729106 -- ------------------------------------------------------- This sf.net email is sponsored by: To learn the basics of securing your web site with SSL, click here to get a FREE TRIAL of a Thawte Server Certificate: http://www.gothawte.com/rd524.html