Hi Wei, I think this is correct. We recompose the whole screen if anything animates. Chris and Michael know the details here. This might be an easy fix if you want to contribute a patch. Though, I am not sure it matters for most hardware whether you composite the entire screen or just a subrect. Again, Chris knows this code and the underlying hardware constraints a lot better.
Regards, Andreas On Feb 5, 2013, at 1:13 AM, Wei Chen <[email protected]> wrote: > Hi Chiajung Hung, > I disabled the battery and signal in status bar in home screen, and put the > whole screen in static, the CPU usage was decreased to 2%, > I add log codes in LayerManagerOGL::Render, it always return > rect.width*rect.height 1920 *1080, every invalidated pix would cause whole > screen render and whole buffer swap ? > > On Tuesday, February 5, 2013 8:51:17 AM UTC+8, Chiajung Hung wrote: >> Hi Wei Chen, >> >> >> >> I think the CPU cost on Compositor is not easy to analyse. If you really >> concern that, I think you can file a bug with more information about your >> platform and give some information about it. (for example, the screen >> resolution, CPU clock and EGL extension set, etc.) >> >> >> >> And I think it is not a static scene if you are charging your battery or the >> wifi icon on status bar change, or the clock on status bar ticks. Basically, >> any small change on screen trigger composition. >> >> >> >> I think you just found the symptom, but the root analysis is far more >> complicate that we can discuss on a bug and then see how we can make it >> better :) >> >> >> >> Best Regards, >> >> Chiajung >> >> >> >> ----- Original Message ----- >> >> From: "Wei Chen" <[email protected]> >> >> To: "mozilla dev b2g" <[email protected]> >> >> Cc: [email protected] >> >> Sent: Monday, February 4, 2013 6:35:07 PM >> >> Subject: Re: [b2g] how to enable hardware compositor >> >> >> >> On Thursday, January 31, 2013 8:31:21 AM UTC+8, Chiajung Hung wrote: >> >>> Hi Wei Chen, >> >>> >> >>> >> >>> >> >>> 1. The hardware composer *do not* help when you concern CPU usage, and >> >>> >> >>> basically *not always* introduce performance gain on Android if the >> >>> >> >> >> >> >> >> hi, Chiajung Hung >> >> >> >> I open the macro COMPOSITOR_PERFORMANCE_WARNING in CompositorParent it >> always says >> >> >> >> Compositor: Composite took 43 ms. >> >> Compositor: Composite took 127 ms. >> >> Compositor: Composite took 79 ms. >> >> Compositor: Composite took 55 ms. >> >> Compositor: Composite took 64 ms. >> >> Compositor: Composite took 67 ms. >> >> Compositor: Composite took 49 ms. >> >> Compositor: Composite took 68 ms. >> >> _______________________________________________ >> >> dev-b2g mailing list >> >> [email protected] >> >> https://lists.mozilla.org/listinfo/dev-b2g > _______________________________________________ > dev-b2g mailing list > [email protected] > https://lists.mozilla.org/listinfo/dev-b2g _______________________________________________ dev-b2g mailing list [email protected] https://lists.mozilla.org/listinfo/dev-b2g
