General Performance

[TolkienBard 58]

I'll start by saying, server performance is still adequate more than 90% of the time. This is less a bug/complaint and more me just trying to figure out how to best tweak or improve what I have, as things are not as rosy as they once were.

My current server configuration is:
Windows 10 Pro
Intel i7 6700K slightly overclocked
16 GB of RAM
Nvidia GTX 960 GPU for transcoding
Approximately 100 TB of media

Recently, in the past two months or so, I have found that certain titles are having stuttering issues. Sometimes a full reset of server and/or client clears it up. More recently, no amount of tweaking could get the 4K version of the Snyder Cut to play on Roku. My brother and I took that to be the result of some changes Roku was making at the time, as those changes were causing streaming issues for other Emby users as well. Most of those appear to have cleared up though. But then, the last two days, I have attempted to watch movies using Emby Theatre on my gaming rig, which has even better technical specs. Usually, any use of Emby Theatre on a PC means ZERO issues. It has been far and away the best/most reliable way to access Emby for us. Now though, I am starting to get more stuttering. Watching a film two nights ago, I got about 20-30 minutes in before all of a sudden, it started to briefly pause, before suddenly starting again. These pauses got longer each time. So, I just paused the stream for about two minutes and that seemed to solve the issue. Then, last night, watching a larger movie with a bigger file, it paused again about 40 minutes in. Then, it took the better part of a minute to start up again before pausing again about 10-15 seconds later. Again, I paused the stream. This time it did not solve the problem the first time around. I wound up pausing the stream for a bit over five minutes while I refreshed drinks and so forth and that longer pause seems to have solved the issue.

The behaviour has me thinking my server is getting over-taxed on trying to transcode more recent 4K films. I know it has had issues since the middle of the summer transcoding Ted Lasso from 4K to an acceptable stream for my 4K Samsung television (though if I use AppleTV to watch it directly, no issues). But, since I have an Emby Theatre PC hooked up to that television, no biggie. So, my question is, where should I be looking to increase performance or to at least get more reliable performance, especially with these newer 4K releases? I would rather not gut the system and start from scratch. That seems like it is likely to be a bit excessive.

I've attached the server logs for yesterday. I couldn't find anything in there that would suddenly slow things down. I did see in the forums a post about the ability to change the db cache size coming up as a feature to improve search performance. I'm looking forward to that. However, my biggest issue is with the recent playback issues and stuttering. Do I need a newer, bigger, badder GPU in order to ask Emby to rely on hardware transcoding? Is something not configured right? I'm looking for suggestions and comments here.

embyserver-63772185594.txt

Edited November 12, 2021 by TolkienBard
mistype of RAM size

[Carlo 4561]

I'm a bit confused.  Are you only seeing these slow downs when working with 4K media?  If so are these HDR or SDR?
On theater when having this issue if you bring up stats for nerds what method is playback?

[TolkienBard 58]

As far as I know, the problem has only been with 4K media, though I could be wrong. I have only started noticing the issue recently. At first, it was not something I gave much thought to, as I assumed at the time it was just a one-off incident.

I reloaded the last movie I remember the issue coming up with to check how ET was playing it. According to Stats for Nerds, it was using direct play. That actually confuses me a bit more as, all the media PCs are hardwired, so there shouldn't be any real issues. Also, if there was no transcoding going on at the time (I'm not sure if there was or not the first time I watched), it doesn't make sense that pausing the film for a short bit would fix the issue.

As to the final point, the 4K media is HDR, which my television supports. Although, 4K HDR media through the Emby for Samsung app has, in the past, had some issues with stuttering as well. But I worry less about that since the Samsung has a media PC attached to it. Also, because the Smart Hub is a few years old now and no longer has room after bloatware to fit the updated Emby app. So, I will likely no longer be using that for now.

[Carlo 4561]

If it were me having issues playing back high bitrate media (I'm guessing based on 4K) through Ethernet to Desktop Theater I would start looking at the environment.  To me based on what you've said this sounds like a network issue. What I'd try and do is bring up performance monitor on the Theater PC if windows and look at the different stats but especially the network. Is it nice and smooth or going up and down a lot?

I'm certainly not saying you have a network issue but it sounds like something to check.  Something like this that's direct playing that pauses is usually either something network related or media related.  You got to start somewhere so looking at what's going on performance wise on the client as well as the server is a place to start.

If you have multiple PCs on Ethernet, try playing back the same movie from another PC.  See if doing anything like this can narrow down the issue.

[TolkienBard 58]

Looks like I know what I am doing tomorrow. I'll report back after running some tests.

[Carlo 4561]

Those are just some general things to look at but feel free to improvise.

Let us know what you find or don't find.

PS if you haven't restarted your cable modem/router in a while that would be a good thing to try as well.

Edited November 13, 2021 by cayars

[visproduction 315]

I noticed another post in the forum talk about variable bit rates.  A side effect may be that encoding is tripped on, if the variable bit rate of the original, goes higher than the setting in Emby to start encoding a lower bit rate copy for playback. Could that be part of this issue?

Also Roku is all Wifi, which can have all sort of issues.  Maybe a good test would be to playback content from the server through the Ethernet connection to the TV and see if the suttering is still there.  If it is, then there is something on the server or Ethernet connection, if not, then it's the Wifi.

Hope that helps.

 

Edited November 14, 2021 by visproduction

[Gilgamesh_48 1240]

9 minutes ago, visproduction said:

Also Roku is all Wifi, which can have all sort of issues. 

Only some Rokus are wifi only. I know the Ultra can be either wifi or wired and I think there is at least one other Roku that has an Ethernet connection. 

Yes, for high bitrate files Rokus are inconsistent via wifi but so are most other streaming boxes. I use Rokus in my home and the ones I use most are wired but I have one that I use wirelessly and it seems pretty much as stable as my wired Rokus most of the time.

As far as the problem in general goes I really think the files above 20gbs  or so are not suited to streaming in general. It is unsurprising that big files have problems on many networks and systems. 

I just avoid ripping anything to anything particularly large and I have no problems the vast majority of the time.

[visproduction 315]

I found a good source of test videos to see at what encoding speed you run into suttering.  https://jell.yfish.us/

[TolkienBard 58]

Appreciate the help. I still haven't been able to drill down on what the issue is, but I have eliminated some variables, so I am at least "making progress". The Rokus are Roku televisions and are not in the house, so I am not going to sweat any of that just yet. I am fairly certain the issues my brother is having have to do with his wi-fi connectivity. We've only ever had one title we could not get to play on his television to save our souls. The solution for that was, he came over and we watched it while putting away some steaks and beers.

My Samsung television is hardwired to the network. It is a 4K HDR television, but it is regularly choking on 4K HDR content that is provided by Emby. If I go outside the Emby ecosystem and stream from the original source, instead of using my captured copy, it streams just fine. Stats for nerds indicates it is attempting to use Direct Play with the rest of the settings on auto. The television also happens to be attached to a relatively robust gaming rig, so when I encounter this issue, it is a simple enough affair to switch input from the Samsung Emby app to PC and just stream it through Emby Theater on the PC. That just means leaving the PC fired up, which is not a big deal now that it is getting cold out. Having the rig warming up a corner of the bedroom is sort of nice when it is below freezing outside. Still, that isn't how it is supposed to be.

My NUC, which is a 4th generation i5 NUC, was also unable to play a 4K movie using Emby Theater. I would select the film and then get the spinning wheel of doom. The dashboard on the server itself recognized that the NUC was signed in, but never even registered that the NUC was trying to play something. However, if I closed out Emby Theater and used Chrome, the NUC was able to handle playing through Chrome like a champ. Because Emby Theater never was able to even load up the movie, I have no idea whether it was going to attempt Direct Play or not. Given that it too is hardwired to the network, I suspect Direct Play is what would it would have defaulted to. The house's wiring is CAT 8, so it seems unlikely there is any sort of bottleneck there. There certainly shouldn't be, though with modern tech, I suppose anything is possible if there is one toggle wrong somewhere.

As far as I can tell, anything that is not 4K HDR streams to all devices just fine. Material that is 4K HDR, may or may not stream properly through Emby Theater on the NUC or through the Samsung app. I have yet to figure out why some will and some will not properly stream, though the number of "not properly streaming" titles is becoming an issue with much greater frequency. 

 

[Carlo 4561]

In this case I would check the specific type of HDR media using a couple sources to verify.  If it's HDR10 Emby should be able to handle it.  But then it's going to depend on the client and if it reports it can play HDR or requires SDR which would case a tone mapped version to be made.

This could be the case with Emby Theater asking for SDR vs HDR.

 

[TolkienBard 58]

Thanks for the sample files.

I guess I know what I am doing with my holiday weekend. Time to narrow this down more and then report back.

[Luke 42081]

Let us know how you get on. Thanks.

[visproduction 315]

I found this report of Ethernet speed required for 4K HDR.  Surprisingly 1 GB Ethernet is barely enough for the lowest res.  This is uncompressed.  So obviously you can't expect non-compressed video to playback well.  I thought there would be a little more headroom.  of course, buffering ahead is fine, but eventually that catches and you get stuttering.  So maybe your Ethernet is not optimal and at 1GB it looks like it will fail with a lot of 4K HDR content.  
https://pro.harman.com/insights/enterprise/education/how-to-distribute-4k-networked-av-over-1-gbps/

So the right compression is going to be important.  It would be nice to get a faster Ethernet.  Up in the higher 4K HDR bitrate range with very low compression then becomes almost impossible to serve the content remotely.  The uncompressed math is really only ever used by post production when the original master is getting effect layers or being edited.

Edited November 28, 2021 by visproduction

[Carlo 4561]

That's uncompressed which no one would use expect those doing mastering. Any Blu Ray of 4K HDR you see will have been compressed with H.265 most likely and be in the 30-80Mb range.  On average a Gb NIC will handle 15 4K streams pretty easily (just do that math).

[TolkienBard 58]

I'm still no closer figuring out a solution, but it does seem to likely be an issue with 4K HDR. I'm just not sure what the issue is yet. I have a Samsung 4K HDR television with the Emby app on it. That app struggles with nearly all 4K HDR titles. I have an i5 NUC connected to another Samsung, this one only a 1080 plasma panel. The current complaint coming from the Mrs is that she cannot watch one of our new movies through Emby Theater. Selecting "Play" simply brings up the spinning wheel of death. However, examining the server dashboard during that time, it does not even indicate that she has attempted to start anything. However, she is able to play the same film using Emby through the Chrome browser. The somewhat beefy gaming PC (hooked up to a Samsung 4K HDR panel) can play most anything through Emby Theater. However, despite having a better GPU and more horsepower than the actual server, it still finds pause/long-stutter delays with some of the more recent 4K HDR titles.

All the computers are hardwired, as is the 4K Samsung. To the nest of my knowledge, everything is working just fine for my brother at his place, no matter what the bit-rate. It used to be, he was the one who would have issues with early pausing for a short bit that would then give way and allow smooth playback. Now, it is almost like the sides have switched places.

[Carlo 4561]

Hi, It sounds like you might need to look for bottlenecks in your LAN or server if the gaming PC is having trouble with the 4K media assuming it's direct playing.

When playing back through the gaming PC on the 4K TV what is the bitrate shown in Stats for Nerds on the client?
Does it show it direct playing?

How many switches or routers are inline between the Emby server and the Gaming PC when connected this way?  If you go through your home router try using a switch instead as your router could be the cause of this issue.  Ideally your router has two ethernet connections only.  One is the incoming Internet and one from the router to your main switch. No packets touch the router unless they are Internet packets.

Those are simple things to check.