[MPlayer-dev-eng] Re: Compile options

[Trent Piepho]

On Thu, 21 Sep 2006, Andrew Savchenko wrote:
> > so perhaps this is the reason why our results differ
> > so much.
>
> For vo or user time it is possible, but, please, tell me _how_ different
> VO can affect VC time?

Different vo (which includes video filters + video output driver) will use
different amounts of memory.  Obviously -vo null is going to use very
little memory, and -vo x11 (which implies -vf scale for YUV -> RGB
conversion and scaling) is going to use a very large amount of memory.

This will effect the CPU cache.  The more code has to be executed to
process one frame the more cache misses there will be.  If the vo code uses
more memory, then the vc code will have more cache misses and run slower,
even though it's the exact same code doing the exact same thing (*) no
matter what vo is used.

(*) Well, there is DR and slices and so on, so it's not that simple.