[NiKRuLeZ]

For 250 mbps at Wifi to be possible, the only thing that can help you is increase the Chunk Size to 512K or 1 MB  (NFS chunk size)

Also you mention NFS. I'm not using NFS in my scenario ... it's all over WebDAV. So will changing the NFS settings help?

It's very simple, please go into the settings and set the values to what was suggested. It's a one time click.

I've set the NFS Chunk Size: 1MB
Buffer Mode: Buffer all network filesystems, including: SMB, NFS, etc.
Memory Size: 256 MB
Read Factor: 4
Chunk Size: 1 MB

Observations: Play 1 - The video starts with the same problem, stuttering, sluggish. then it pauses ... the cache (grey bar) grows and there is smooth playback but this is very short lived until the playback bar reaches the end of the cache bar (so the two are in sync with each other) then it starts to stutter again ... and towards the end of the same process will repeat .. by this time the video clip is over.

Play 2 - The entire clip stutters throughout and the actual clip takes 56 seconds to finish.

The above hasn't really made any difference.

Debug on:

250 mbps bitrate file playing over wi-fi:

Showing 121% but really throughout it was hovering around 150% throughout the video clip



When playing the 400mbps bitrate file from the flash USB attached drive (to the shield) the CPU averages around 60%.

The CPU when playing over wifi is definitely higher (sometimes more than double when playing from usb flash storage)

[fritsch]

Good - that's the FileCache thread ... busy and overloaded reading data chunks from wifi. That needs an entirely new concept inside kodi with a proper analysis why the CPU load is so high in general. I mean it's kodi thread - not a kernel thread. Maybe we simply copy the 40 MB/s one time too often around ... and that makes the difference to other players.

Do you by chance know how large the CPU load is when you do your iperf3?

It's the same on FireTV and others. Too slow Single Core performance will cause the FileCachethread simply not being fast enough.

As you say VLC is perfectly fine with the same webdav share - could you post a VLC log as well? With the proper debugging visible?

[NiKRuLeZ]

Good - that's the FileCache thread ... busy and overloaded reading data chunks from wifi. That needs an entirely new concept inside kodi with a proper analysis why the CPU load is so high in general. I mean it's kodi thread - not a kernel thread. Maybe we simply copy the 40 MB/s one time too often around ... and that makes the difference to other players.

Do you by chance know how large the CPU load is when you do your iperf3?

It's the same on FireTV and others. Too slow Single Core performance will cause the FileCachethread simply not being fast enough.

As you say VLC is perfectly fine with the same webdav share - could you post a VLC log as well? With the proper debugging visible?

I'll try get all this to you by the end of this week.

But for now, at least we're getting closer to the problem at hand.

Do you think post analysis it's a refactor of code within Kodi and do you think this will be high priority fix or something longterm? Just a general idea.

[fritsch]

I think the shortterm solution would be to use a LAN cable :-)

[NiKRuLeZ]

I think the shortterm solution would be to use a LAN cable :-)

LOL neat solution!

But in seriousness, is the FileCache problem on the roadmap to be investigated/anaylsed/fixed?

[jogal]

But in seriousness, is the FileCache problem on the roadmap to be investigated/anaylsed/fixed?

Hipotesis: FileCache is the cause of problem.

Test with Cache disabled   (GUI Settings > Services > Caching -> Buffer mode > No buffer)

any change?

YES: confirmed.
NO: FileCache is not the root cause.

VideoPlayer has 8 seconds of internal cache. Not needs use FileCache for streaming inside LAN. In fact is not used for Blu-Ray's, ISOs, etc.

[jogal]

Possible tests:

• Disable Cache --> GUI settings > Services > Caching > Buffer mode > No buffer
  

[fritsch]

The time / size in bytes video player allocates might only cover 4 seconds or a bit less with a 250 MBit/s stream. I think you changed the calculation to 4K Blu-ray UHD max last time this file was touched.

Still curious to see.

[NiKRuLeZ]

The time / size in bytes video player allocates might only cover 4 seconds or a bit less with a 250 MBit/s stream. I think you changed the calculation to 4K Blu-ray UHD max last time this file was touched.

Still curious to see.

If I understand this correctly ... then when I play the 140mbps bitrate file, it keeps up with the cache buffer in front of the actual play back (just about ... sometimes the playback reaches the cache buffer ... the grey bar i'm talking about ... and it sometimes pauses to let it grow more and the playback continues). 160mbps bitrate and files above this rate all stutter.

I'll do the above test and get back to you ...

[NiKRuLeZ]

Possible tests:

• Disable Cache --> GUI settings > Services > Caching > Buffer mode > No buffer
  

Just carried out this test.

Didn't make a difference, all the bitrate video files above 140mbps (160, 180, 200, 250) were all stuttering throughout the playback.