CPU & Memory Settings

In the CPU & Memory pane, you can view and configure the CPU- and memory-related settings.

To open these settings, choose Actions > Configure > Hardware, then click CPU & Memory.

VM_Configuration_CPU and Memory

Option

Description

Processors

Use this menu to change the number of virtual CPUs allocated to your virtual machine.

Memory

Use this menu or slider to change the amount of memory allocated to your virtual machine. To optimize the performance of both the virtual machine and macOS, set the memory allocated to the virtual machine to be somewhere within the recommended range.

Extended memory limit (available in Parallels Desktop for Mac Pro Edition only)

This option allows you to allocate more memory to a virtual machine than your Mac physically has. Use this option with care (or your system may significantly slow down) and only in rare cases. For example, when you're trying to install a database in to the virtual machine and the installer claims that you don't have enough memory.

Hypervisor

In this menu, you can choose whether to use the hypervisor from Parallels or from Apple. You're recommended to use the Parallels hypervisor.

Adaptive Hypervisor

Select this option to set Parallels Desktop to automatically optimize performance for the virtual machine or macOS depending on which application you're working with at the moment. When you're using a virtual machine app, more resources are given to the virtual machine, and when you're using a macOS application, more resources are given to macOS.

Enable nested virtualization (available in Parallels Desktop for Mac Pro and Business Editions only)

Select this option to enable nested virtualization support. Parallels Desktop allows you to run:

  • Hyper-V virtual machines inside Windows 8, Windows 10 and Windows Server 2012 virtual machines;
  • VMware ESXi virtual machines;
  • Xen and kernel-based virtual machines in versions of Linux that support Xen and KVM.

Note: Running a virtual machine within a virtual machine may dramatically slow down the macOS and virtual machine performance.

If you use Parallels virtual machines to build, debug and test applications, enable nested virtualization to install and work in:

  • Android emulator for Visual Studio;
  • iPhone emulator for Visual Studio;
  • Xamarin.Android;
  • Android Studio;
  • Embarcadero RAD Studio;
  • Docker for Windows;
  • Microsoft Visual Studio + TwinCat 3 (support for TwinCat 3 is being tested and there may be some bugs).