I've noticed that Parallels seems to use less CPU when at idle. A Windows SP3 VM on parallels idles at 0.5 to 1.5%. On Fusion, the CPU usage is usually low but on some kind of schedule spikes to ~9%. See more reviews for Parallels Desktop Parallels allows you to run Windows and Mac applications side by side. Choose your view to make Windows invisible while still using its applications, or keep the familiar Windows background and controls on your Mac. Now my mac gives high CPU usage under Parallels desktop and fans are always running at full rpm. CPU usage for prl_client_app is around 45% and gaming feels extremely laggy. I've assigned 4 GB RAM and 4 cores to my virtual machine. Parallels Desktop 14 makes it a snap to run macOS, Windows, or Linux virtual machines on your Mac. It has improved launch times, graphics improvements, and automatic monitoring of storage, CPU.
Symptoms
- My computer fans speed up and Mac starts to heat up.
- My virtual machine's process (prl_vm_app or Parallels VM) in the Activity Monitor consumes 100% of Mac CPU or above.
Cause
High CPU usage by virtual machine's operating system.
Resolution
Maximum utilization of every CPU unit assigned to a virtual machine in Activity Monitor counts as 100%. For example, if your virtual machine has 4 CPU units assigned, then a total amount of CPU utilization by a VM will be 400%. To check how many CPU units are assigned to VM open configuration window > Hardware > CPU & Memory.
NOTE: We highly recommend using the recommended number of CPUs. Assigning more recommended number may cause performance degradation of both Mac and virtual machine.
Users who uses their virtual machines rarely may encounter slowness and other performance issues after starting a virtual machine if it wasn't used a long time. From our side we recommend to give Windows some time to finish doing necessary internal jobs and other required maintenance tasks. If Windows still working slowly, check Task Manager as described below to find out the reason of CPU consumption.
Virtual machine's CPU consumption directly depends on guest operating system usage. If you notice that your VM consumes a high amount of CPU resources, check CPU consumption in guest operating system in Task Manager (right-click on Windows task bar > Task Manager):
Once you determined what process of Windows program consumes sufficient amount of CPU, you may refer to the software manufacturer knowledge base to find more information. For some types of software, like video or photo editing, CAD or videogames, high CPU usage is a common operation condition.
If you find that this process belongs to Windows OS, please note that the following system actions cause high CPU usage:
- Downloading and installing Windows updates
- File indexing
- Driver incompatibility issues
- Redundant startup applications
Parallels Mac High Cpu Usage
To find out the reason for high CPU usage in your case, note the process name and refer to Microsoft Support or a third-party resources for more information.