Mac OS High CPU Usage

I’ve had similar ongoing issues with high CPU usage on a 2018 Mac mini running Mojave, i5 processor, 32GB ram, ethernet connection only. Setup Roon Core on the Mac when it was new May 2019. Initially launching Roon would spike the CPU for a few minutes and then level off, typical for graphic intensive databases rebuilding cache files. Persistent high CPU usage started showing up in August 2019, 200+% CPU load on launch after startup of Mac. Wouldn’t drop to normal levels. Had to quit the app. Sometimes it would run up the CPU just sitting idle for no apparent reason.

I’ve found a fix and a possible reason for the issue. When the processor starts ramping up and staying up, turning on wifi, enabling network interface en0, even if it’s just for a second before turning it off, stops the high CPU usage for me. It seems like a system call in Roon is being made to en0, and if it doesn’t receive a response, the CPU load maxes out. While having 2 active network connections is not best practice, I’ve settled for having both an ethernet and wifi connection active. Since this I haven’t had a single high CPU instance with Roon. YMMV

I think the issue of WiFi may have come up on a thread. In my case, I don’t use wifi on my desktop so I don’t think that is it - at least in my case.

My main point is that this is not a new problem and has existed for some time. @noris has not responded, nor has anyone else from support. I tagged him her just so he cans see this string is alive. If the solution has been posted elsewhere, perhaps he can post it.

I have this same issue happening on my Mac Mini as well. I have the same config as you except, I am running Catalina, I also never have the wifi turned on as well. I did turn it on and my CPU utilization immediately dropped as well. I then turned it off and the utilization remained low.

I have not beed a roon user very long, but very concerned this thread has been going on for over a year. I will add I don’t experience this on my older Macs.

Hello All,

Please see Dylan’s update on this issue here:

@noris Any updates? I have given up trying to use Roon on my desktop. After all this time, I think it is reasonable that we get an update every week or so.

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@support right, weekly updates would be great instead of having to ping you.

Hi @Jon_Saperia/@mavmcl,

There is no update at this time but once we have an update we will share. The CPU issue is definitely a priority for us, but it is a tricky issue to nail down, so we appreciate your patience here while we work on it.

I’m running Roon Server on my MacBook Pro and it ran OK for the last two weeks, but today I woke the Mac up and the Roon Server was running at a whooping 400% heating the CPU to more than 90 degrees, which is just below this CPUs thermal limit.

MacBook Pro (16-inch, 2019)
2.3 GHz 8-Core Intel Core i9
16 GB 2667 MHz DDR4
Wifi: OFF
Bluetooth: ON
HDMI output to a Samsung TV

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Hi @Anton_Podolsky,

Can you please try toggling your WiFi On/Off to see if it helps with the issue when it occurs? We’re still looking into this behavior to try to identify the root cause but other users have reported that toggling WiFi helps resolve this issue when it occurs.

Had the same problem. Toggle Wifi ON resolved it.
I’m connected to my network over a LAN-Ethernet adapter so i had Wifi switched off.
The Core runs on a different Server(Linux) so it was a little bit strange was caused the high CPU.

MacBook Pro (16-inch, 2019)
2,4 GHz 8-Core Intel Core i9
64 GB 2667 MHz DDR4
Version 10.15.6

Same issue:

MacBook Pro (16-inch, 2019)
2.4 GHz 8-Core Intel Core i9
64 GB 2667 MHz DDR4
Bluetooth: OFF
Roon Version 1.7 (build 571)
macOS 10.15.5 (19F101)

Turning WiFi on solves. The fix remains if I then turn off WiFi. Is this a phone home gone wild? What the heck does WiFi have to do with Roon?

I use ethernet because I use a Micro Rendu. This problem has only started recently. It is using almost 100% of each of the 8 cores.

Last time I noticed this I just restarted the Mac and that seemed to stop ikt. Not today. There was no interruption to the music so it could have done this many times without me being aware. Today I am sitting right next to it so I hear it above the muisc.

How very strange. I did as suggested and turned the wifi on and of a couple of times and the wifi is now off again and Roon dropped from using 900+ to 11!

Why is no one an swwring these questions. My Roon is just unusable now. I have tried the wifi thing again but to no affect this time. I have shut the Mac down, restarted it, all to no avail. I cannot play music at all because it isn’t safe to have my CPU running at almost 100%.

It’s safe to have a processor running at 100 just not optimal.

And you hear the whirring over the music. This is a serious problem with the program but it seems the techs don’t think so. The last time anything was said by support was 27th July. I’m still waiting for another problem to be resolved but it’s months since anything was said to me about it.

Hi @Knitman,

We are still looking into this issue, for any updates please refer to the main thread here:

We have heard from a few users that upgrading to Big Sur helps with CPU usage, so if you are running an older version of MacOS, I would try to upgrade if possible.

Thank you. I feel more confident about the upgrade knowing this. Have not done it though. Today, it did rise for a while but only to 83 ish. Then it dropped down to 4 something and stayed there. No whirring fan.

(Am having a bad time neurologically speaking. I try to correct all my typing errors but know I don 'y catch them all.)

Perfectly clear.

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