I have performance issues in VirtualBox, the quest operating system runs really slow and laggy.

The configuration:

  • Host: MBP 2019, 2.3 GHz 8-Core Intel Core i9, 16 GB RAM, MacOS Sonoma 14.2
  • Guest: Kali Linux, up-to-date, XFCE
  • VirtualBox: 7.0, Base memory: 8192 MB, 8 CPUs, Video memory: 128 MB, VMSVGA, Enabled 3D Acceleration. Guest addition is installed.

I tried different graphics controllers and also to turn on and off the 3D Acceleration. I tried different views: scaled mode, just scaling it down etc.

None of these seem to work. I also don't find good Google hits.

  • 1
    We need more detail on the Mac, because 8CPUs & 8GB assigned to the VM sounds a little over-generous, swamping the Mac itself, but tbh, VB is just slow compared to Parallels or Fusion.
    – Tetsujin
    Commented Dec 15, 2023 at 11:32
  • I added the info to the question.
    – SiGe
    Commented Dec 15, 2023 at 12:17
  • 1
    OK, with an 8-core HT CPU, you're OK to set 8 cores in the VM [assuming the VM can use them effectively]. 8 out of 16GB total RAM might be just a little over, I'd drop that back to 6. The rest will just be VB being slow, I'd have thought. I presume you're running the VM from the Mac's internal SSD, or something similarly fast?
    – Tetsujin
    Commented Dec 15, 2023 at 12:23
  • I am posting from a Kali machine here. I use well under 1/2 my host memory for my Kali machine. I use only 2 cores for CPU. The VM works well. Try assigning less host resources to the VM. I also use VMware instead of VBOX.
    – John
    Commented Dec 15, 2023 at 12:58
  • I tried with the suggested settings, but it is still slow. Especially when I start Firefox. But the slowing down is random. I have a feeling that is due to the high resolution that caused by the Guest Addition resizing, even though I switched to a fixed size. (I have this issue with other Linuxes too, but just after installing Guest Additions, but that I need in this case.) The difference is that I'm using VBox. I would like a free solution, VMware seems to not have a free plan.
    – SiGe
    Commented Dec 18, 2023 at 10:37

2 Answers 2


As David mentioned in the comments, I switched to a free VMWare instance that doing the job very well.


Have you tried booting with mitigations off? I seem to remember that VirtualBox did not handle well the Intel CPU vulnerability mitigation management (which, on a personal system, shouldn't be an issue).

They did get to fix that, but maybe on MacOS it still doesn't work as it should.

In the kernel parameters at boot,


See also here.

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