iClock vs Apple Clock CPU usage

CPU usage is going to be more than Apple's clock, since iClock is doing more (creating the color image in your selected font and displaying the date).

Using the following settings:

iClock and Apple Clock

One Sample CPU usage using Process Viewer:

Description of Test System: Mac OS 10.2.4, Power Macintosh DeskTop (450MHz, Single G4 with 384Mb Memory)
CPU Usage

Why is iClock using more CPU then other Applications?

Some processing are 0.00 when are in the background, because they are doing nothing. If you are activily using them (Typing in a dialog, opening/updating a window, downloading) then they will use more CPU. Apple Clock (listed above as SystemUIServer) and iClock are doing something very second, so they will take up CPU time every second. Process such as BBEdit Lite are in the background doing nothing so they take up 0.00 CPU.s Process such as Internet Explorer (listed above as Explorer) are in the background, but recently used so the CPU readign will be going towards zero soon.

Why does it bounce up an down?

All the CPU monitoring software is "sampling" the CPU usage. Since iClock is updating every second, if the sample hits the same time iClock is doing something (updating the Menu Bar, opening a window) the value will be larger. If the sample hits in between updates and not using iClock menu, it will be smaller.

How do I decrease iClock CPU usage?

To reduce CPU usage of iClock set the time format to not display seconds.


 
Last Modified: 21 Feb 2003