[MPlayer-dev-eng] Re: [patch] A-V sync tuneup, round 2

[Arpi]

Hi,

> >> of frametime between two frames.  it's maybe sounds scary, but 10%
> >> is enough for A-V sync
> > all this should be optional until we see it doesn't break anything and
> > works better on all systems.
>  It can be completely disable by the '-nodapsync' command-line option, but
> may be a 'configure' option too.  how I should do?

your patch has lines with no if(use_dap_sync) before. for example resetting
relative timer. it will break timing code.

> >> ps# Arpi, it contains some bugfixes and improvements since previous
> >> version, IMHO it's much cleaner and stable
> > previous was too messy to even read, not talking about apply. this one
> > is a bit better, but you should add more comments or do something, as
> > it's hard to understand what is why.
>  that was just a framework..  well, I've just now begins to learn english,
> so about the technical things I'd write a private mail in hungarian :}
i prefer well commented (english! :)) patches.

> > btw, comment for your note: it is not intel clock limitation or so,
> > it's linux limitation, especially kernel configuration. value of HZ
> > defaults to 100, it means 100 task switches per second. as usleep()
> > releases mplayer process and allow scheduler to call something else
> > (idle?) it will took n*10ms to get the cpu back. note, that on SMP
> > systems it isn't true.
> > note2: HZ can be set to 1000 at kernel compile time.
>  I'm afraid to change it's worth, because it can decrease the system
yes it will.

> performance, maybe I'm wrong..  BTW, there can be more context switch than
> HZ, isn't it?
afaik no. at least usleep() depends on HZ.

> > note3: RPC timer should be used for timing based on 8khz clock.
> > note4: RPC is usually disabled for 'average' users. and HZ=100.
>  hm, I didn't think on it, cause I had never enabled it. :} it's a Good
> Thing, I'll test it tomorrow.. but softsleep even required by non-linux
> platforms and RPC-less users
non-linux platforms usually have well-working usleep()
and rtlinux has too.


A'rpi / Astral & ESP-team

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