Will vm run windows noticeable better from a bootcamp partition than running straight from macos?

You don't appear to understand how you can run Windows.

1. You can run Windows natively (using 100% of your system resources) using Boot Camp
2. You can run Windows or in a virtual machine, Parallels, Fusion, or VirtualBox.
3. You can install Windows using Boot Camp then use that installation as the target system in the Parallels virtual machine.

If you use Boot Camp natively Windows will use all your system resources to run. (fastest option)

If you use a virtual machine, Windows and MacOS will be running simultaeously each using your system resources at the same time. (slower option)

Running Windows in a virtual machine is "noticeably" slower than running Windows with Boot Camp. Windows in Boot camp uses all your system resources. Running in a virtual machine Windows needs to share your system resources with your MacOS.

The article is about running Windows with Parallels assuming you already have Windows installed. The only benefit as the article points out is you can run Windows & macOS at the same time. You can do that without installing Windows using Boot Camp.

Viking is correct, either way, 4GB is not enough Ram.

The only difference is how you access the windows data: from a partition or from a parallels file containing the windows OS. Windows thinks it's running on a bare machine. Windows, when run in a parallels vm, will present disk addresses to macOS like it would on a bare machine. MacOS will have to take these addresses and read the data for the vm.

(1) I have no idea how Parallels sees the partition. Let's assume there is some way for parallels to get direct access to the partition. Thus parallels would not need to translate the address into reading from a file. It could pass the addresses directly to macOS. MacOS would do some verification on the address and read the data and pass back to parallels.

(2) when windows is stored on a file. Parallels would have to translate the windows disk access into into a file offset. I don't this would take much processing. It turning a disk access into a file offset: basically two or three multiples and three adds. It passes this file offset to macOS. MacOS converts the files offset to a disk access.

The biggest will be if the data is stored on a rotating drive or a SSD. A rotating drive could result in a lot of disk arm movement because windows will be looking at the drive differently than how macOS has stored the data. This could be mitigated by some disk fragmentation software.

Anyway, having the data in a file as apposed to a partition could result in more processing cycles spent when access data from a file. The biggest factor still will be the speed of the drive.

Others have reported it doesn't make much difference. I've explored why that is so.

R

Right from the beginning of this thread you were told that running Windows in Boot Camp uses all your system resources which makes running Windows in Boot Camp faster. You were told that running Windows in a VM causes each operating system to run concurrently thereby sharing system resources. You then wanted to know the speed difference between options 2 and 3 which I presented. There is no difference between 2 and 3. Both options 2 and 3 use a VM. Option 1 as explained is the fasted option but you wanted the difference between option 2 and 3.

The difference between option 2 and 3 is not speed but the ability to choose at any session whether to boot directly into Boot Camped Windows or to run Windows in the VM. It is the same single install of Windows. If you choose to boot into Windows its performance will be faster than if you choose to boot into MacOS then run the same installed Boot Camped Windows using the VM.

I don't know what type of virtualization parallels does. Here is a quick write up on virtualization.

https://securitywing.com/types-virtualization-technology/

I guess I should do some type of performance testing.

Parallels Desktop uses a special type of virtualization: a hardware-assisted full hardware virtualization

that relies on Intel VT-x technology and allows for simulation of the

whole computer with its hardware and software. This simulated

environment is called a virtual machine (VM) and enables a Virtual PC on your Mac.

Virtual Machines (VMs) for macOS - Mac ... - Parallels

Robert

No difference.

Okay well I tried.

Here is Windows 10 Professional running on my iMac. Which has 32GBs of RAM.

It's running in VMWare Fusion. Same thing.