Overclocking to improve playback performance?

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dddd
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Re: Overclocking to improve playback performance?

Post by dddd » Thu Feb 04, 2021 10:58 pm

I have a slight overclock on pi3B but not specifically to do playback. (It would be nice to newbies if Pi updated the comment about what the Pi1 overclock freq is, seems like they're trying to trick them into underclocking.)

I noticed vast problems with myth keeping up with playback when I upgraded from myth 29 to myth 31. I was able to mostly eliminate it with the dtoverlay of fake kms (see above).


However here are several other things I'd already done that others might not have been doing:

Reducing the HDMI desktop resolution from 1080 to 720 produced a significant improvement in performance.

using OpenMAX EGLFS instead of MMAL produces a slight (but detectable to my eye) performance improvement. I haven't checked lately if still required, but as part of my setup I did this:
link opt_vc_lib_libbrcmEGL so to usr_lib_libEGL so
link opt_vc_lib_libbrcmGLESv2 so to usr_lib_libGLESv2 so

increasing the GPU memory to 384 helped slightly


Still not good enough performance to turn on deint on, even to
Low (tested with 1080i recording).

dddd
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Re: Overclocking to improve playback performance?

Post by dddd » Fri Feb 05, 2021 9:14 pm

oh forgot one thing that helped slightly:
echo "vm.swappiness=5" >> /etc/sysctl.conf

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monkeypet
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Re: Overclocking to improve playback performance?

Post by monkeypet » Tue Feb 23, 2021 1:57 am

The Raspberry Pi 4 is mostly unusable watching MPEG2 unless you overclocked it. I've been operating it overclocked with a fan for almost 1 year now. It is working fine now after some recent OS updates. I discuss my experimentations to get more performance in the thread viewtopic.php?f=46&t=3791. I haven't touched it in awhile now since it has been working well for me.

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