iMac Idle CPU Utilization

Running my Roon server on MacOS High Sierra on a Core 2 Duo 3.06 Ghz. It runs and playes great but… something is strange.

No DSP and not even playing CPU Utilization stays at close to 60% - what does Roon do?
I’d understand if it does something, but it just sits in memory and still utilized the cpu @60%, this doesn’t look normal.

It may not look so but for the on macOS it usually is. Maybe this has something todo with the underlying software architecture (using mono and stuff). Do you notice anything indicating a problem besides seeing a high resource usage in Activity Monitor?

Nothing else appears to be a problem. It finds my endpoints, plays seamlessly. It just when an application is not in use, it drops its cpu usage.
It might have to do with architecture if it does indeed use mono. Hate generalizing, but in my experience, the most of cross-platform frameworks do this kind of job

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Try running Roon Server as a different user (log out first), and see if the phenomenon reoccurs.

That processor–Intel Core 2 Duo Processor E7600 (3M Cache, 3.06 GHz, 1066 MHz FSB)–isn’t really up to the job of Roon server and falls well below the minimum specification. So, whilst it is working, the computer is going to work hard and Roon is likely to be a little sluggish on the UI.

I do get that Core 2 Duo is below the minimum specification. UI is not sluggish at all and I have not observed any other downside to it besides the artifact of high CPU Utilization. It is not even making the computer sluggish for other tasks, which tells me that this particular CPU is pretty good despite being too old.

I’ll try to run Roon on my Core i7 laptop tonight, just to see.

Take a look here as a guide:

And the recommended i3 NUC:

Got to try it on 3.1 GHz Intel Core i7.
Din’t add my full library, just a few files to make sure nothing “overloads” Roon.
It all comes back to the same question. While idle even on i7 CPU Roon is using way way too much of it, more than 100%, but since it is a multi-core cpu it is not noticeable unless you know where to look. Here is my top with Roon line:
13533 Roon 135.8 01:19.91 56/1 3 428 453M+ 1784K 0B 13533 1 running *0[5] 0.00000 0.00000 501 251755+ 19555

After running for a while it goes down but never too low, something between 40 and 70%.
You can say it is ok, but it is very unusual nowadays to see something like in this in activity monitor and eventually it translates in the amount of energy our computers use.
So it has nothing to do that I used it on a not recommended spec CPU, both computers have SSD(to illuminate that idea), but something how this application is written.

Constant CPU usage seems to be a ‘normal’ thing… (on MacOS?!?)

~10% constant (literally 24/7) on a 2017 vintage CPU here.

:sob: :worried:

@davewantsmoore is ~10% on Windows or Linux? Which version?

I knew something was amiss.
Started going over all the settings and under “Settings/Library” found “Background Audio Analysis Speed”, there clearly was visible that it is processing some files. After it finished, CPU utilization came down to normal values.

I’m happy to report that even on Core 2 Duo CPU(which is below recommended specs), on macOS, on almost a 10 year old iMac(upgraded with SSD) Roon performs flawlessly. The music library resides on external RAID 5 array, connected through an old firewire connection.

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The roon client (not core, just a player/controller) uses ~10% CPU when it is idle (not playing, not updating anything, etc.) This usage continues 24/7.

The CPU is a 2017 i5.

" even on Core 2 Duo CPU(which is below recommended specs), on macOS, on almost a 10 year old iMac(upgraded with SSD) Roon performs flawlessly."

I agree. There is no usability (slow down) problem with the client. It is just that when not using the client… it sucks a (seemingly) large amount of processor cycles.