Priority of Roon Server *under macOS*


Is there a simple way to lower the priority of RoonServer under macOS (Big Sur)? I moved my instance of RoonServer from a dedicated MacBook Pro to a multipurpose Mac mini with an M1 chip, a 256GB SSD, and 8GB of RAM, plus a much faster Ethernet port. The sound quality has improved a lot, but all of my Apps from Chrome to Photoshop to Pages and even Mail have slowed down from being almost instantaneous to having a notable delay. If I lower the priority of RoonServer, I may be able to recoup some of the performance of the other Apps and not excessively compromise the much better sound quality I now have.

Andy Schaub

Under normal usage on a M1 Mac mini RoonServerr doesn’t use a great deal of the CPU. However, it does tend to use quite a lot of RAM, so this may be what’s causing the problems in your current setup. Next time you’re trying to run RoonServer alongside other RAM hungry apps (e.g. Photoshop) take a look at the memory tab of Activity Monitor, particularly the Memory Pressure graph at the bottom of the screen along with the info provided to the right of the graph. If memory pressure is high, or there’s excessive swap used, this may well account for the slow down.

Darn, I wish I’d known that. I would have gotten more RAM; having said that, the SSD should be a very fast swap drive for virtual memory, and all of my data is on external drives, so the SSD is mostly used for loading Apps and buffering one kind of data or another. It’s not as fast as RAM, but it should really perform faster than it does, I think, unless Roon somehow hacks the OS to get “pure” RAM.

Do they do that??

No, but it does tend to use a fairly large amount. Have a look at the memory pressure graph and see what it shows. I’ve found - even with 16GB of RAM - that running Photoshop and RoonServer at the same time can put me into ‘yellow memory pressure’ - ‘Your computer might eventually need more RAM’. If you end up in the red this indicates that you have insufficient RAM to meet the needs of the apps you’re running.

Hi David,

I launched the Activity Monitor and looked both at the CPU % and amount of RAM used by RoonServer when I play music through one zone.

It uses as much as 17% of the CPU on occasion but is almost always in the 5%-6% range. Also, (again) running just one zone and doing almost no DSP, RoonServer uses less than 1GB of RAM, consistently about 770MB. So that’s great.

However, I almost always play music when I work and leave the Roon “remote” App running out of habit. By comparison, it’s a pig!! :slight_smile: Just joking; however, it does consistently use about 20% of the CPU and a full 1GB of RAM.

I think that must be because Roon, very intelligently, uses a portable graphics gaming engine and library (Unity) as a portable environment for the Roon “remote” App user interface.

This gives the listener-user a very rich experience across a number of different OS’s and types of devices, but games are not known for being “lightweight” Apps and the use of Unity does incur some overhead, I am sure.

In any case, I decided to just “Quit” the remote App when I wasn’t actually selecting an album to play, and that gave me back almost all of the snappiness I thought I had lost because of RoonServer, which was wrong. Roon Radio helps a lot in cases like this, but there are also playlists, double albums, streaming Internet radio, etc.

It does make me think that, rather than getting a RoonServer-dedicated Mac mini, iMac, MacBook Pro, Nucleus[+], SGC i5, etc, picking up an iPad Mini and putting it on a stand on my desk by the Mac mini would be a great way to have a “dedicated Roon remote” to avoid the issue of running the remote App on the server machine all the time in case I feel like jumping from song to song.

I had an SGC i5 for a while, and it’s a very nice machine; but using my multipurpose Mac mini as a partial RoonServer machine does sound better (not that it’s a 100% fair comparison) and offers many advantages over a “headless” machine with no keyboard, mouse, monitor, or incremental backup software, particularly in paradoxical situations where I could not access the i5 via a browser because, say, the network card failed or the card’s driver crashed, and then I had to plug in a keyboard, mouse, and monitor and hope that I had remembered to make a manual backup to an external drive both before and after the last update, else Fed Ex the i5 to Vermont for $35 each direction to be “restored”.

While I can appreciate the elegance of having a Roon Nucleus, SGC i5, i7, etc, or an Innuous Zen sitting next to my Rega Io, it makes a lot more sense to me to get a nicely-equipped MacBook Pro 13 and use it to run almost nothing but RoonServer with an external USB drive (running Time Machine) and a hardwired Ethernet connection, sitting on the top shelf of my equipment stand with a DAC or preamp underneath it.

That’s what I did before I got the Mac mini, I just couldn’t afford two new computers and I needed to use my MacBook Pro 13 for something else. Even if you wanted to load Ubuntu onto said MacBook Pro and install RoonServer for Linux (!!!), you’d still have a keyboard, mouse, and monitor in an elegant package that you put on top of your component stand.


Photoshop is a behemoth; and it’s not very good at using multiple cores. It needs A LOT of RAM; having said that, my old machine was a 27" quad-core i7 iMac with a 3TB Fusion drive and 32GB of RAM.

It was great in its day, but as I started to work with medium-format digital and had Capture One, Photoshop, the DxO Nik Plugins, and a 16-bit Canon pro printer dialog and driver all running at the same time with multiple 60GB TIFF files, it started to really slow down (but it worked). Running RoonServer was not even an option.

By comparison, the Mac mini is a breeze, and its an entry-level model; but the use of the M1 chip, the fast albeit paltry 8GB of RAM(*), and the speedy 256GB SSD with all LaCie and G-TECH external RAID drives for data and TimeMachine backups via Thunderbolt helps to separate things out and keep thing fast.

The third-party, 24" Dell 4K HDR display is a real step up from my old 27" non-Retina iMac; and I used a videophile-quality AudioQuest Pearl HDMI cable for stunning images. Plus, the gigabit Ethernet and my AQ Diamond and Vodka RJ/E cables give me lighting-fast Internet and LAN throughput, resulting in much better sound.

I guess what I mean by all of this is that, when you become a multiple App “power user” (no joking), it seems that your computer performance needs increase almost exponentially rather than by a factor of 1, 2, 3, 4, etc., and that kind of sucks. :frowning:

(*) A friend kindly financed the Mac mini “CPU box thing” itself while I paid for everything else, so I was limited in how much I could spend; else, I would have gotten at least 32GB of RAM and a 512GB SSD, but separating things out means that I can upgrade the “CPU box thing” on its own in a year or two and not repay for the display, keyboard, mouse, RAID drives, etc.; and that seems like a “sound” decision. :slight_smile: :slight_smile:

I’m glad you got it sorted. I also made the same decision as you recently when I swapped out my ageing MacBook Pro for the mini. I’ve now got a couple of 4K LG monitors, separate keyboard and trackpad, and a bunch of decent external drives (including a 1TB NVMe I use as a scratch disk and for Roon backups). I did go for 16TB instead of 8, and a 1TB hard drive, but I’ll also be able to swap out the ‘CPU box thing’ at a later date without sacrificing any other gear.

One further thought, that might help your current situation: I’m using at app called App Tamer, mostly to limit the CPU resources available to things like Dropbox, Time Machine, Spotlight, Google Drive and so on - all of which can hog the CPU and impact on the smooth running of Roon. One of its features is that it allows you to completely stop an app that’s not in the foreground. You could use this to halt the Roon app when you’re not using it. This wouldn’t help with RAM usage, but it would free up some CPU cycles.