Icons screensaver sucking too much CPU?

[humdinger]

This is hrev43696.

I love the screensaver "Icons". But judging from ActivityMonitor it seems to suck a bit too much CPU for what it is doing. Between 15 and 20%, I'd say. I have a Core2Duo, 2ghz, 2gb RAM and a supported Nvidia GForce 7600 GO in this notebook.

Can anyone see an easy optimization of the code?

[axeld]

Not having looked at the code, the easiest option would always be to lower the frame rate.

[jscipione]

Humdinger, can you retest this on your machine on a revision sometime after hrev46759?

On a virtual machine I'm seeing minimal activity above baseline when running Icons.

[humdinger]

I captured the time the Icons screensaver is active with ActivityMonitor, see the attached screenshot. The white horizontal line is the 50% mark. So it seems to vary between 25% and 50%. I guess the peaks is where the icon fading takes place. This is with hrev46974.

[humdinger]

ActivityMonitor log when Icons saver is active

[humdinger]

The above was with default scheduler setting in ProcessController, i.e. "Low latency".
Here's the same capture with "Power saving" (which BTW tends to freeze my machine sooner or later...):

[humdinger]

...with scheduler setting "Power saving"

[pulkomandy]

I don't think we can do better. Alpha blending pictures in software is a cosly operation. as axel says, it would be nice to have an option in the screensaver settings to change the framerate.