[mythtv] Speed of mythepg?

Isaac Richards mythtv-dev@snowman.net
Sun, 27 Oct 2002 09:46:37 -0400

On Sunday 27 October 2002 02:33 am, Justin Hawkins wrote:
> Hi folks,
> Just wondering how fast I should expect mythepg to be?
> On my Athlon 1.2 it takes about 1 second to scroll left and right. I have
> 5 channels. I also have an few gaps in my program guide around midnight,
> which return back 'unknown' in mythepg. However, scrolling to these items
> takes about 5 seconds. As you can imagine this makes it quite difficult to
> see what movies are on tomorrow night :-)
> I've narrowed down part of the problem. My MySQL server is not localhost.
> There is a lot of traffic needed to scroll (from watching my quite
> unscientific tcpdump :-), and about 5 times as much traffic when 'unknown'
> programs start showing up.
> My MySQL server is not that grunty (P233MMX) but, it's not that much
> information right?

The major slowdown right now is that it looks up every program for every 5 
minute interval right now..  It wasn't as bad a design issue back when it 
only dealt with 30 minute intervals, but Andrew's changes to make it more 
accurate display-wise are making it do it every 5 minutes, and thus 
generating 6 times more lookups.  The thing to do would be to only look up 
each program once, and skip ahead to the next one without hitting the DB 
server for the extraneous data..  It'd be a little bit of work, but if anyone 
wants to submit a patch to do it before I get to doing it, that'd be welcome.

> I appreciate that some sort of lookahead would be a tricky proposal, but
> what about a toggle setting that would cause scrolling to be 'page flip'
> style - so that when you hit the left or right edge an entire page of new
> programs is produced. This at least would mean the performance hit would
> be all in one go.
> Alternatively, a different set of keystrokes (page up, page down?) could
> move entire pages, while left and right arrow preserve their current
> behaviour.

I was pondering this right before I left on vacation -- took awhile to scroll 
through a week's worth of programs to select what I wanted.  So yeah, I've 
added that to my TODO list.