[mythtv] Profiling myth

[James Courtier-Dutton]

Hi,

I would like to add some performance profiling to myth.
I think a good place to start would be to try and measure the user experience.

First metric will be measured from the mythfrontend app:
a) Time of channel change event. I.e. New channel number entered
b) Time of first video frame appearing on the screen from the new channel.

b - a = Channel change latency.

I think (a) is quite easy to do, as one can identify the event and
just add a log message into the method implementation.
The only thing complicating (a) would be if there are multiple points
where it can occur. E.g. Users selects a recording to watch instead of
just changing channels.

I think (b) is harder to get.

Has anyone already done this?

Once I have this metric, I can start modifying code and be able to
tell if I am really improving it or not.
I will also be adding intermediate metrics, but first getting (a) and
(b) right is the most important.

Kind Regards

James