I’ll compare Parallels 1.9.4 AppStore Edition vs UTM 4.5.4 (100). Time of writing of this blog post: 8. Oct. 2024.

Parallels is much more expensive. Requires a license which need to be purchased on a yearly basis and costs 120 eur. Compared to that, UTM App Store edition costs 10 eur one-time only. Parallels AppStore Edition is massively outdated when compared to Parallels downloaded from the Parallels web site.

Parallels starts Ubuntu VM much quicker. On my MacBook Pro M3, Ubuntu fully starts in 10 seconds, while it takes 23 seconds to start the Ubuntu VM in UTM. However, this looks to be a problem with UTM drivers: virtio-gpu-gl-pci causes Ubuntu to start slowly, while virtio-gl-pci starts Ubuntu blazingly fast.

UTM is able to boot and install off ubuntu server ISO coming straight from Canonical; Parallels just breaks if you try that, and you have to stick with whatever Parallels downloads for you - potential privacy/security concerns as the origin of the ISO is unknown.

Parallels is closed-source while UTM is open-source.

Both UTM and Parallels support 3d acceleration; even YouTube videos play and seem to be accelerated. I haven’t measured the CPU usage and effectivity of the video play; native video playback on host OS is definitely most effective and that’s what I’m using.

Intellij IDEA works:

• UTM accelerated only runs Intellij in Wayland mode. IDEA works very well in this mode.
• Parallels runs Intellij in both Wayland and Xorg mode correctly.

Parallels App Store Edition is severely crippled compared to UTM:

• MacOS in VM: UTM auto-magically downloads the installer and installs guest MacOS single-click style, while Parallels App Store Edition doesn’t support guest MacOS at all - you need to download the full Parallels app for that.
• Parallels App Store Edition doesn’t allow you to resize the linux guest hard disk (!!!) - you need to create a new disk and mount it somewhere, to get more disk space. This releases all sorts of hell in IDEA - IDEA just hates when opening projects from symlinked path (or having .m2/repository on symlinked drive), tries to resolve the files and then duplicates them - just crazy quirks all over the place.
• Parallels App Store Edition doesn’t support newest Linux kernels. Kernel 6.8 boots, but dmesg shows scary UBSAN: array-index-out-of-bounds in /var/lib/dkms/parallels-tools/1.9.4.23885/build/prl_tg/Toolgate/Guest/Linux/prl_tg/prltg_call.c:143:21 segfaults and Ubuntu later shows the crash report window.

Input capturing: Parallels auto-captures the input so that ⌥⇥ and ⌘␣ are captured by linux rather than host MacOS, and does that seamlessly. Compared to that, UTM requires you to manually capture the input. UTM supports auto-capture but the mouse cursor jumps to a different place in screen, the mouse movements acceleration changes slightly and is slightly laggy; the overall feel is that Parallels offers much more polished experience. UTM is however usable.

Both shared folders and clipboard sharing works well; UTM allows only one shared folder though. Shared folders are mounted automatically by Parallels; in UTM you need to follow the UTM Linux Sharing Guide; the VirtFS option worked for me well.

When logging in to Linux, UTM would randomly pretend that Ctrl is pressed (or Alt) all the time. That means that you can’t type with keyboard and mouse clicks randomly don’t work or show crazy menus. The only way is to logout and log back in. Very annoying and frustrating. The solution is to avoid pressing any modifier keys until Linux-in-UTM fully boots and you log in.

UTM Blockers

Some Linux apps DO NOT WORK in UTM with 3d acceleration/gpu: the apps will only display a blank rectangle, and the only workaround I found is to boot with the virtio-gl-pci driver. I suspect that all xorg/xwayland apps do that. Examples:

• Citrix Workspace ARM64 remote desktop - no known workaround, disable 3d acceleration.
• qemu-system (VM-in-a-VM); workaround: use -vnc :0 and connect a VNC viewer to localhost:0.
• Intellij in xorg mode: enable Wayland mode
• vice and uae c64/amiga emulators: no known workaround, disable 3d acceleration

Reported as UTM #6968.

Conclusion

UTM supports newer Ubuntu and sticks to standards (the SPICE protocol) and is much better privacy-wise but has its quirks. Parallels (the AppStore Edition) offers a bit more polished experience UI-wise, but the drivers are closed, they taint kernel and throw strange segfaults on Ubuntu 24.04+. The support from Parallels is horrible, and the strange UI blinking in Linux and segfaults persuaded me to switch to UTM.

However, if you need to run X apps then UTM won’t work for you. This is quite a blocker.