Performance Issues

[Norm258]

I have things just about perfect but performance hits are still an issue. All too frequently video begins to studder for about 30 seconds then continues on. Really bad when the wife wants to watch her program.

Investigations indicate that mplayer runs at about 67% cpu normally but when it hits these studders, it jumps to 90 to 100% cpu, which causes the playback issues.

The hardware is an AMD dual-core 2.6Ghz. Separate NVidia 8400 video card.

Running Ubuntu 8.10, Sagetv 6.5.11 (I believe) both server and client on the same machine.

Input is always HD coming from an HD-PVR. I have selected "fair" as my video quality which is the lowest - wish I could get more out of it.

A solution would be to get vdpau working with the video card, but Sagetv doesn't support it

Mplayer has been optimized with:
framedrop="1" # For slow machines
nocorrect-pts="1"
lavdopts=lowres=2:threads=8:fast=1:skiploopfilter="all"
in the .mplayer/config file.

Not sure what else I can do other then to split the frontend/backend? Any suggestions on how to improve the situation?

Thanks
Norm

[fract4l]

Is this for recorded shows or for live TV? Are you watching them using the client or placeshifter?

If it is a recording have you tried watching the file directly by using vlc player or some other media player to see how the machine handles the video without running through sagetv?

[SuiDog]

I haven't looked into this with linux but I know when I was running another product on a windows system it made a HUGE difference when I used the hardware decoder (using the gpu of the video card) vs the software decoder. I also was using the same box for as the frontend and backend and I was having performance issues.

Looking real quick at some Myth info for Ubuntu it looks like you need to enable mplayer to use XvMC. I don't know if the Sagetv client for linux uses it but it's worth investigating.

I'd take a look at http://www.mythtv.org/wiki/XvMC#NVIDIA about using XvMC on ubuntu. It maybe will lead you down the right path.

I have no idea if this will help but to give you and idea the utilization on my windows box went from 80-90% utilization when watching livetv (recording and playing at the same time) to about 20-30% once I enabled the hardware mpeg decoder on my 5200fx.

Suidog

[Norm258]

Thanks for the info but xvMC isn't available for the 8400 series I run. Support was discontinued a while back for it because of vdpau.

I know vdpau would really improve things because it did when I was running mythtv.

This is for livetv as opposed to recordings.

I am running linux server with linux placeshifter (no client available for linux) on the same box.

Norm

[SuiDog]

Even when watching live TV it still records it (well at least I this is the case by default) unless you have found a way to disable it. Thats why you can pause live tv. Even when you are watching it, it should show a record in the upper right and it's also why there is a couple sec pause when you switch channels.

I may be wrong but I don't think so.