Issue with recording TV episodes and streaming at the same time

[johnny_swindle 5]

A few day back, I attempted remotely to stream a movie while I was at a friend's house. All was going well when suddenly the screen froze. Paused the movie and hit play and it played for a few minutes and froze again.

I remoted into my server and saw that three recordings were taking place using my HD Prime.

After searching the forum, I think I may know what my problem. If I am off base, please correct me.

If I am reading things correctly, each recording temporally gets transcoded before being placed into it final location. The movie, was being transcoded. I think I I was over whelming the system. If I build another emby server just for recording who that eliminate this issue?  Or am I simply asking too much from my network.

 

Thanks

[MBSki 1009]

I'm currently testing solutions to the same issue. Which client are you using? It DOES seem that on the Android TV client at least, that transcoding both for recording and watching causes a conflict in the transcoding folder. At the moment I'm experimenting with a dedicated SSD for transcoding both recordings and streams. So far I havent had any freezes in this setup, but I plan to test some more before I call it a success.

I would guess that your solution would also work, but if a separate hard drive for transcoding does the trick that might be an easier solution. 

[johnny_swindle 5]

I am using Roku TV. Does the recording and streaming use the same temp cache location?

[Luke 37024]

1 hour ago, johnny_swindle said:

I am using Roku TV. Does the recording and streaming use the same temp cache location?

Yes 

[johnny_swindle 5]

Based on this new information, for me, I think I will build another Emby server just for recordings and point the primary server at the recordings. That way I hope I will eliminate the issue that I am experiencing.

[MBSki 1009]

@Luke This isn't a solution. We can't all be creating multiple servers just so we can stream and record at the same time. Can you at least add another transcoding path for the DVR so we can put the transcodes on separate disks?

@cayars Have you run into this issue? I'm still testing with a dedicated transcoding drive, but the stream I'm watching does still seem a bit sluggish when recording at the same time. Are there any other options you can think of? 

[Carlo 4330]

2 hours ago, mbarylski said:

@cayars Have you run into this issue? I'm still testing with a dedicated transcoding drive, but the stream I'm watching does still seem a bit sluggish when recording at the same time. Are there any other options you can think of? 

The best way to fix IO issues like this is to add a SSD drive to use for transcoding and DVR.  Here's a cheap 240GB drive from amazon for $28. I like to think of these as throw-away drives.  Abuse them as need be without worry as you'll never have actual data on it to loose. No sense spending $150 on a drive for transcoding and then worrying about pre-mature drive life from writing small files to it over an over again.

To be honest besides a slight speed difference really only noticed running IO benchmarks it's hard to feel the difference between a drive like this and an expensive Samsung 980 Pro.

But anyway even the slowest of SSD drives is going to be orders faster then the fastest rust drive.

[johnny_swindle 5]

@cayars

Even though both processes us the same cache location, is this the recommended solution for those who are having issues? So the cache location will be set to the SSD (recording and transcoding) and recordings will go to a tradition hard drive?  Have I got this correct?

Edited December 17, 2021 by johnny_swindle
spelling

[MBSki 1009]

13 minutes ago, cayars said:

The best way to fix IO issues like this is to add a SSD drive to use for transcoding and DVR.

I'm still not sure this works though @cayars. I'm still seeing a performance hit when the DVR and stream are both using the same dedicated drive for transcoding. I think a coding change is needed to add a custom location for the DVR transcoding. that would make it even better right? It would give users the option of completely separating the DVR and stream transcodes.

[Carlo 4330]

I've been pretty vocal about some things that could be changed to reduce IO in this situation and we've talked about it internally as well. We are looking at what can be done short term to help but don't want to get into a situation of duplicate work since we have a much bigger project already incorporating different ways of handling this so it won't be an issue. If we pull people to work on this we just delay the real solution that much more.

So yes, there could very well be some additional improvements short term if possible but it's not logical to start re-writing big parts of code that we know is going to be replaced. Currently in beta for example we have some changes to the transcoder that will enable more streams to play back direct vs needing conversion. Also better handling of Closed Caption as well.  So yes we continue to make changes to improve the overall Live TV experience and know every little bit helps.

Speaking purely as a user of the system and from first hand knowledge in my environment I was running Emby on an older i7 with Nvidia GPU. I had an SSD for the OS/Emby (C drive) as well as a dedicated SSD used for transcoding and DVR. Prior to the SSDs I'd have issues at times especially trying to skip commercials on long foot ball games or trying to catch up.

About 6 months ago I switched to a Synology 920+ which is Celeron based with Quicksync. Even though the box has a 4 disc RAID I immediately had trouble again with IO when recording and playing back foot ball games.  I ordered two 1 Gig NVMe sticks and configured them as read/write cache for the array and immediately was able to have 4 games recording and play back of two games with FF working.  It makes a huge difference in my environment for sure.  I would imagine if using 5400 RPMs it would be worse than I saw with 7200 RPM drives as well.

 

[johnny_swindle 5]

If I started a "small flame war", I apologize. I understand that a permanent solution is in the works and that is a good thing. The thought of having an SSD for the cache never crossed my mind.

I will get an SSD and use it and will look forward to future versions of Emby.

BTW, I really enjoy Emby and it has made my video viewing experience a pleasure.

[MBSki 1009]

1 minute ago, johnny_swindle said:

If I started a "small flame war", I apologize. I understand that a permanent solution is in the works and that is a good thing.

LOL, not at all. We love discussing this topic and I personally learn so much from folks jumping in and adding their experience.

2 minutes ago, johnny_swindle said:

BTW, I really enjoy Emby and it has made my video viewing experience a pleasure.

  Me too! It still needs a few things, but I've pretty much given up on Plex at this point and Emby is my only media server now. 

21 hours ago, cayars said:

I've been pretty vocal about some things that could be changed to reduce IO in this situation and we've talked about it internally as well. We are looking at what can be done short term to help but don't want to get into a situation of duplicate work since we have a much bigger project already incorporating different ways of handling this so it won't be an issue.

Thanks @cayars! Glad to hear a fix is in the works. 

[Carlo 4330]

For any of you wondering about using an SSD via USB3 the testing has begun:

Hit the first snag in testing trying to get some baseline numbers so any ideas would be appreciated.

[johnny_swindle 5]

My SSD just arrived and I won't be able to do any testing until after the holiday. But I will report back.

[johnny_swindle 5]

I completely forgot about this post. I installed my SSD and switched the cache to that drive.  I am not sure if it made any difference.  The problem that I am encounter is with recorded content. Sometimes it plays flawlessly and other times it won't play. I will patiently wait for future versions to see if that solves my particular issue.

[Luke 37024]

On 7/1/2022 at 1:36 PM, johnny_swindle said:

I completely forgot about this post. I installed my SSD and switched the cache to that drive.  I am not sure if it made any difference.  The problem that I am encounter is with recorded content. Sometimes it plays flawlessly and other times it won't play. I will patiently wait for future versions to see if that solves my particular issue.

Hi @johnny_swindle can we please look at an example? Please attach the information requested in how to report a media playback issue. Thanks !

[johnny_swindle 5]

Hi Luke.....

I believe the issue that I may be encountering is with the pc build, and my network. However, when I do encounter the issue again, I will post.

 

[Luke 37024]

1 hour ago, johnny_swindle said:

Hi Luke.....

I believe the issue that I may be encountering is with the pc build, and my network. However, when I do encounter the issue again, I will post.

 

That would be great, thanks !