LMS takes all COU and becomes unresponsive

[TurnipMan]

Hello,
Asking for help as to how I troubleshoot this.
When I play a radio stream, in particular LBC my LMS service ramps up to take all CPU and then it is unresponsive to changes like volume up/down.
It's running on a PI 4 and TOP shows 100% CPU.
How do I dig into what is consuming the CPU?
Thanks
Tom

[Paul Webster]

I think this has come up in the last year or so and there was a fix to one of the audio handlers.

Which version of LMS are you running?

[TurnipMan]

Currently 8.2 it did the same on 8.1

[Paul Webster]

So that leaves you 8.2.1 and perhaps 8.3 to try.

[Paul Webster]

I just tried LBC ( https://media-ssl.musicradio.com/LBCLondon ) on SqueezePlay (old - on Joggler) with LMS running on a 4-CPU Raspberry Pi (pCP).

Logitech Media Server Version: 8.2.1 - 1644703015 @ Sun 13 Feb 2022 01:08:32 AM CET

"top" shows 24.6% utilisation ... but that is one CPU running at 90%+ ... which I presume means LMS (single threaded) is stressed.

However, my player cannot handle it natively so it is being transcoded.
"top" shows that faad and flac are involved but those two applications are only using 0.2-1.5% CPU.

Perhaps someone with a recent 8.3 can report how it is for them.

When running "top" the "c" key will show performance per CPU at the top of the screen.
"q" to quit.

[slartibartfast]

I just tried LBC ( https://media-ssl.musicradio.com/LBCLondon ) on SqueezePlay (old - on Joggler) with LMS running on a 4-CPU Raspberry Pi (pCP).

Logitech Media Server Version: 8.2.1 - 1644703015 @ Sun 13 Feb 2022 01:08:32 AM CET

"top" shows 24.6% utilisation ... but that is one CPU running at 90%+ ... which I presume means LMS (single threaded) is stressed.

However, my player cannot handle it natively so it is being transcoded.
"top" shows that faad and flac are involved but those two applications are only using 0.2-1.5% CPU.

Perhaps someone with a recent 8.3 can report how it is for them.

When running "top" the "c" key will show performance per CPU at the top of the screen.
"q" to quit.

Hmm when I first started playing LBC using your URL to a Pi mpd player CPU was 25-26% but after a short time it has returned to 2%.

Sent from my Pixel 3a using Tapatalk

[TurnipMan]

So that leaves you 8.2.1 and perhaps 8.3 to try.

OK I'll do that, how stable is it?

Also perhaps important I have two Squeezelight players synced up, one on a PiCore Player and the other on a windows PC

[slartibartfast]

OK I'll do that, how stable is it?

Also perhaps important I have two Squeezelight players synced up, one on a PiCore Player and the other on a windows PC

Do you see the same with other radio stations?

Sent from my Pixel 3a using Tapatalk

[TurnipMan]

Do you see the same with other radio stations?

Sent from my Pixel 3a using Tapatalk

No, I regularly synchronise up to four players with BBC stations from the Sounds plugin.

This has not happened for long; afraid I can't be sure when it started.

[paul-]

The default process tools are provided by busybox, so they are a bit limited.

you can add extensions with more full featured tools.

htop (Has a little better thread and subprocess view capabilities.)
procps-ng (provides full versions of top and ps)

But likely its something in LMS itself. So logging is likely the best options. If I recall the cpu utilization issue and unresponsive was related to tmp file handing. LMS was generating a ton of tmp files and keeping the file handles open. This issue was seen after LMS was running for a while, and restarting LMS would solve the problem for a while. I forget which versions of LMS has this correction, likely only 8.3