[MPlayer-dev-eng] [PATCH] A new ASS renderer

[Reimar Döffinger]

On Tue, Sep 25, 2012 at 12:31:42AM +0400, Vladimir Mosgalin wrote:
> perf record/report output seems mostly meaningless, though. For example
> ass-fullscreen-karaoke vs ass-window-karaoke tests - big difference in
> CPU usage but same perf output.

The perf output says rather clearly that MPlayer in both cases uses
330K CPU cycles.
I see very few possible explanations and none of them make sense
1) Your CPU executes vastly fewer cycles per second in the fullscreen
case
2) Vastly more CPU time is spent outside MPlayer in fullscreen mode.
This is quite an issue since a process being able to cause a huge
additional CPU usage that is not accounted to it is a rather nice DoS
tool.
3) The CPU usage actually is the same for both

Have you run all these tests with the CPU forced to some fixed
frequency? I'm not keen on ending up debugging TurboBoost issues for
example.

> Or "isolate_freepages_block" which
> appears only in glhack version (that's with your patch), but strangely
> taking way more CPU usage in window.

As you can see from the EOSD stats printout the windowed mode behaves
significantly different. In particular, the modified code is used
only very little in fullscreen mode, since most glyphs are larger
that 64x64 pixels (which I do not understand at all, almost all
are smaller that 64x64 for me with the same screen resolution -
my best guess is that I do not have the right/same fonts installed as
you).

> Neither mplayer output nor perf seem to reflect how much mplayer was
> lagging in gl-fullscreen-karaoke and glhack-fullscreen-karaoke modes,
> with massive actual A-V difference due to sub rendering lagging so much.

Hm, also run those tests with vsync disabled.