Re: [Gnash-dev] A thought about performance

[Rob Savoye]

On 05/12/2010 12:15 AM, MÁTÉ Gergely wrote:

> I mostly use Firefox and sometimes I open 5-6 tabs or even more at the
> same time. In such cases, when all of those pages contain several Gnash
> instances, the general performance of the whole system can degrade to an
> almost unresponsive level.

  This is the unfortunate side effect of the forking & exec'ing the
standalone player, I also have many tabs open, and suffer through the
"too many gnash's running" all the time.

> One possible way may be to automatically pause those instances which are
> in background tabs and thus unseen. Probably some heuristic diagnostics
> should prevent this if there is any network transfer or the instance is
> playing sound, or such.

  While I think this is a good idea, it would need a config file
setting, as some people would want them to run in the background. (like
when trying to download a stream to disk). I had another idea the other
day that might help too. Gnash has a timer that when it wakes up, it
advances frames and does processing. The idea was that much of the time
nobody is interacting with the flash while it's being played. So maybe
we don't want to wake up as often, which would lower the cpu load. We
could change this if the mouse moves, and "wake up".

  For example, when playing YouTube waiting for someone to click "Pause"
keeps Gnash in a tight polling loop. But it you aren't moving the mouse
in the window, why bother to check anything ? At that point Gnash is
just a video player.

  Way back in the very beginning of Gnash, I did a similar technique
where the interval for the polling could be changed while playing flash
by sending an XML message. This lets me crank up the speed for some
animations, and to lower it for others, all under control of the swf file.

        - rob -