Webclient slow reloading recording list after playing a recording

[BrettB]

I am using the latest version of NextPVR (3.5.7) with the webclient to X-NEWA on an RPi 2. I have noticed that sometimes after playing a recording, it exits back to the Recordings list, but it takes several seconds for it to update. It seems like this situation happens more often when the recording service is recording several shows at the same time, but I'm not sure if that is just coincidence.

The situation just happened again after I watched a CSI: Cyber. I captured the logs which are attached. In looking at the webclient.log, I see that the RELOAD_RECORDINGS took 13 seconds between LoadList@1 and LoadList@2.

Code:

2015-11-05 22:44:15.681    [DEBUG][1]    LoadList@1
2015-11-05 22:44:28.892    [DEBUG][1]    LoadList@2

In other instances, the time between these steps is sub-second:

Code:

2015-11-05 09:09:43.056    [DEBUG][1]    LoadList@1
2015-11-05 09:09:43.131    [DEBUG][1]    LoadList@2

Code:

2015-11-05 22:44:33.043    [DEBUG][1]    LoadList@1
2015-11-05 22:44:33.108    [DEBUG][1]    LoadList@2

What is NextPVR doing between @1 and @2? And why would it sometimes take many seconds?

[sub]

Between those two points it's loading the list of recordings from the database, and checking the files exist on disk before including them in the results. It'll be doing the exact things each run. Are you maybe recording to a network drive? If so, windows might be taking some time to re-establish the network connection. Particularly after a period of inactivity. Otherwise it could just be waking a drive or something similar.

[HarryH3]

I see that many of the UI functions are slower when my server is busy recording several shows. It is even more noticeable just after shows have ended recording and more new shows have just started recording. Comskip is also busy with just-ended recordings at this time. I just attribute it to the computer just being too busy to stop and serve up UI stuff instantly. It has to time-slice CPU, disk drive, memory, and network capacity with so many things going on at once. Perhaps if I had a beefier server it wouldn't be so noticeable, but it is usually just a few extra seconds.

[BrettB]

Between those two points it's loading the list of recordings from the database, and checking the files exist on disk before including them in the results. It'll be doing the exact things each run. Are you maybe recording to a network drive? If so, windows might be taking some time to re-establish the network connection. Particularly after a period of inactivity. Otherwise it could just be waking a drive or something similar.

I've got 3 recording directories and all are local drives. I wonder if it has something to do with disk caching and memory available (i.e. when several recordings are occurring at the same time, more memory is used to cache the recordings and it flushes out the directory info from the unused recording drives).

[BrettB]

I see that many of the UI functions are slower when my server is busy recording several shows. It is even more noticeable just after shows have ended recording and more new shows have just started recording. Comskip is also busy with just-ended recordings at this time. I just attribute it to the computer just being too busy to stop and serve up UI stuff instantly. It has to time-slice CPU, disk drive, memory, and network capacity with so many things going on at once. Perhaps if I had a beefier server it wouldn't be so noticeable, but it is usually just a few extra seconds.

I've got a quite beefy server now (just upgraded a few months ago)--it has an eight-core processor, 16 GB RAM, SATA III drives, gigabit wired network, etc. And I've got it only running 1 comskip instance at a time. So I don't think that is my problem. Plus, when I do have this issue, it is not just for a "few" seconds, it is 10-20 seconds as shown in that log. As sub mentioned, I think that it must have something to do with NextPVR trying to verify that all the recordings still exist on disk.

[BrettB]

Between those two points it's loading the list of recordings from the database, and checking the files exist on disk before including them in the results. It'll be doing the exact things each run. Are you maybe recording to a network drive? If so, windows might be taking some time to re-establish the network connection. Particularly are a period of inactivity. Otherwise it could just be waking a drive or something similar.

Sub, I have <AutoRemoveMissingRecordings>false</AutoRemoveMissingRecordings> in my config.xml. So would it still be checking for the existence of each recording every time the recording list is loaded? And, if so, is there a specific reason? It seems rather inefficient.

[sub]

If you have either <CheckForRenamedRecordings> or <AutoRemoveMissingRecordings> set to true, then it'll do these checks.

[BrettB]

If you have either <CheckForRenamedRecordings> or <AutoRemoveMissingRecordings> set to true, then it'll do these checks.

Ah, ok. My config did have <CheckForRenamedRecordings> set to true. But I'm not doing any transcoding, etc., so I don't need for it to be true. I'll change it to false and see if my problem goes away.

Thanks for the quick responses!

[HarryH3]

Here's how I hope to speed up the UI on my server: I'm going to be upgrading the SSD in my wife's laptop around Black Friday. My plan is to use her old one in the NPVR server to host the OS and NPVR. My hope is that this will greatly speed up NPVR's database functions. Right now, just paging down through the EPG takes 2-3 seconds per page, while the spinning disk clatters away to find all of the data it needs to fill each screen.

[BrettB]

Here's how I hope to speed up the UI on my server: I'm going to be upgrading the SSD in my wife's laptop around Black Friday. My plan is to use her old one in the NPVR server to host the OS and NPVR. My hope is that this will greatly speed up NPVR's database functions. Right now, just paging down through the EPG takes 2-3 seconds per page, while the spinning disk clatters away to find all of the data it needs to fill each screen.

I have had an SSD for the system disk on my NextPVR server for a few years now. And paging down through my EPG (or recordings lists) is basically instantaneous. So I would bet you will see a noticeable improvement.