Setting Custom CPU Cores to macOS VMs

Fixing High CPU Usage & Setting Custom CPU Cores on macOS VMs (Proxmox)

In this video Harvey shows you how to fix the **High CPU Usage** and set **Custom CPU Cores** on your virtualized macOS VM using our updated method for Proxmox.

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Important Information macOS only accepts CPU cores in **powers of 2**:

**1, 2, 4, 8, 16, 32, 64, ...**

We provide a workaround to use non-power-of-two core counts. ⚠️ This may or may not work for your system. If you encounter issues, simply revert the changes.

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1. Editing Your VM Configuration

Open your Proxmox VM config:

sudo nano /etc/pve/qemu-server/[VMID].conf

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Intel CPUs

Add the `-smp` line for your desired number of cores to the end of your **Args** line.

Then in **Proxmox → Hardware → CPU**, set:

**1 socket + 4 cores**

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Intel: Supported Core Configurations

Native (No Args Needed) These core counts work natively in macOS:

• **2 cores**
• **4 cores**
• **8 cores**
• **16 cores**
• **32 cores**

Intel: 48 Core Examples

Two working options:

-smp 48,cores=2,sockets=24,threads=1,maxcpus=48

-smp 48,cores=2,sockets=12,threads=2,maxcpus=48

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AMD CPUs

For AMD users, replace your current `-cpu` argument with:

args: <default-arg> -cpu host

Then simply set the desired number of CPU cores in **Proxmox → Hardware → CPU**.

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