Web UI slow to load

Synology DS1019+ NAS running Channels DVR pre-release 2021.02.13.1800
There was a point this morning the web UI wouldn't finish loading.
I looked at Network Inspector and it was showing a crazy amount of requests where normally you only see subscribed status updates every few minutes.
Seems to have settled down now and I'll keep an eye on resource usage if it happens again.

Caught it but not sure what's going on.
No recordings, playback or comskip going on.
Log doesn't show any activity.

Diagnostics might capture what's causing the issue.

Just happened to my other NAS DS1513+ running the same Channels DVR version.

Do you have imports and strmlnks? That’s what is causing the slowdown.

The server in my M1 Mac mini slowed down to a crawl with imports. I mean a crawl, deleting tool for ever. Browsing the server pages took a while. Launching any clients took a while.

All clear after I took the imports out, now it’s screaming fast.

Synology DS1019+ 0183a503-b99d-40b9-96fe-43aa2638b36b
Synology DS1513+ ad560681-a504-485d-9018-8338483b7748

Yes, but nothing added to them lately. Has to be something in the DVR code that changed recently.

Take out the imports on one of the Dvrs and test. It fixed my slowness.

The Mac m1 can comskip a half hour show in 34 seconds, a two hour show in 4 minutes but if you have imports, you will die waiting for something load, delete or navigate.

I'm seeing the web UI is making a lot of repeated requests to the backend for some reason, causing the high cpu usage and lagginess.

Which screen of the web UI are you on? Does it make a difference?

This doesn't really make any sense. Maybe if you had tens of thousands of imports (i.e. if you pulled in the entire streamlinks repository).

No, it doesn’t make sense but it’s true. 14k tv show episodes, not unreasonable if your importing your library, no streamlinks at all.

I've got Import directories setup on both but I'm just testing small samples.
One NAS has 0 Imported recordings, the other has 173.

I'm 'tailing' the Status Events from both NAS's (curl -Ns -m 7200 http://x:8089/dvr/events/subscribe)
and don't see anything unusual when the CPU usage spikes. Actually I'm passing the curl output through jq and redirecting output to a log file, then tailing the log file with Notepad++.

I don't see anything in the DVR log or events when this happens.
Since I originally posted it's happened 3 times on one NAS.
There is corresponding network send activity happening at the same time as the CPU usage spikes.

With http logging enabled can you see which requests come in during that time and from which IP.

Enabled. If I send diagnostics right after it happens will you see the http logging?

Just happened again, 135db9e5-5bf0-4c99-97b3-ea6790952658
About 17:08:50 local time

The requests are coming from, presumably via an open browser window on that machine.

Yes, that's my Windows PC using Firefox to access the web UI.
I just closed that web browser tab at 5:30pm and won't reopen it until recordings are done tonight.
Not sure why so many requests, most of the time the browser was sitting at the main settings screen.

Aman, if you look at the http events GET "/dvr/events/subscribe"
Do the times seem off to you?
i.e. 1h59m59s was me logging for 2hrs, but the rest?

2021/02/14 16:47:07.813671 [HTTP] | 200 | 48.823545515s | | GET "/dvr/events/subscribe"
2021/02/14 16:47:21.785961 [HTTP] | 200 | 13.503223743s | | GET "/dvr/events/subscribe"
2021/02/14 16:48:47.653107 [HTTP] | 200 | 39.346589286s | | GET "/dvr/events/subscribe"
2021/02/14 16:49:08.515908 [HTTP] | 200 | 1h59m59s | | GET "/dvr/events/subscribe"
2021/02/14 16:51:29.726655 [HTTP] | 200 | 34.555734096s | | GET "/dvr/events/subscribe"
2021/02/14 16:54:44.774886 [HTTP] | 200 | 49.261561201s | | GET "/dvr/events/subscribe"
2021/02/14 16:56:50.857740 [HTTP] | 200 | 2.825011012s | | GET "/dvr/events/subscribe"
2021/02/14 16:59:48.360558 [HTTP] | 200 | 4.108589354s | | GET "/dvr/events/subscribe"
2021/02/14 17:00:16.259811 [HTTP] | 200 | 7.821580517s | | GET "/dvr/events/subscribe"
2021/02/14 17:04:35.146378 [HTTP] | 200 | 21.549877471s | | GET "/dvr/events/subscribe"
2021/02/14 17:05:20.436670 [HTTP] | 200 | 23.693474577s | | GET "/dvr/events/subscribe"
2021/02/14 17:05:54.280918 [HTTP] | 200 | 28.455956028s | | GET "/dvr/events/subscribe"
2021/02/14 17:08:42.224751 [HTTP] | 200 | 1.065664415s | | GET "/dvr/events/subscribe"
2021/02/14 17:10:09.632768 [HTTP] | 200 | 47.361539645s | | GET "/dvr/events/subscribe"
2021/02/14 17:14:39.505566 [HTTP] | 200 | 2m41s | | GET "/dvr/events/subscribe"
2021/02/14 17:27:42.565740 [HTTP] | 200 | 1m3s | | GET "/dvr/events/subscribe"