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

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

I'm going to install bootcamp win10 on an old macbook only 4gb ram (saving for a new one, will be a while), I also want to later buy parallels for linux and windows (stretching it thin I know), I read you can run it off the bootcamp partition, that will not be as good as switching at boot and giving all resources to win, but will it be noticeably better than running win 10 direct from mac?

Parellels website addresses this, but only says they are both 'ok' performance, I don't know what that means, both windows will be light usage, no graphics, games, just few applications.

https://www.parallels.com/ca/products/desktop/import-bootcamp/

MacBook

Posted on Sep 10, 2020 7:30 AM

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Answer 1

Sep 10, 2020 8:41 AM in response to GGarrett2

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

You can run Windows natively (using 100% of your system resources) using Boot Camp
You can run Windows or in a virtual machine, Parallels, Fusion, or VirtualBox.
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)

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Answer 2

Sep 10, 2020 7:51 AM in response to GGarrett2

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.

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Answer 3

GGarrett2 Author

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Sep 10, 2020 8:08 AM in response to dialabrain

I understand, but parallels can run from macOS 'off the bootcamp partition' or not

https://www.parallels.com/blogs/how-to-run-boot-camp-in-a-virtual-machine/

https://kb.parallels.com/112941

I am wondering if there would be benefits running off the bootcamp partition.

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Answer 4

GGarrett2 Author

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Sep 10, 2020 8:11 AM in response to VikingOSX

I understand 4gb is not a good amount of ram to run it, but does fit within their stated minimum performance

https://www.parallels.com/ca/products/desktop/resources/

If it suck.s too much in the trial, I'll just delete it and do bootcamp, but I want to try it.

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Answer 5

dialabrain

Level 10

130,319 points

Sep 10, 2020 8:15 AM in response to GGarrett2

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.

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Answer 6

GGarrett2 Author

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Sep 10, 2020 8:20 AM in response to dialabrain

https://www.parallels.com/ca/products/desktop/import-bootcamp/ makes a distinction between the 3 modes, so that's why I was wondering if there would be performance differences, still not sure if there will be, I guess I'll try and see as I'm installing bootcamp anyway (which might not even run well on 4GB RAM), but that's all I have for now.

Good thing there's a free trial.

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Answer 7

GGarrett2 Author

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Sep 10, 2020 8:53 AM in response to BobTheFisherman

BobTheFisherman wrote:

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.

I have no idea why you think I don't understand what a vm/bootcamp is, it's not rocket science, I was clear in my question, all i was asking is if there will be any performance differences between 2. and 3.

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Answer 8

rccharles

Level 6

12,991 points

Sep 11, 2020 2:16 PM in response to GGarrett2

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

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Answer 9

GGarrett2 Author

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Sep 11, 2020 2:25 PM in response to rccharles

Thanks for the throrough examination, I'm going to have all three options so I guess I'll do trial and error to see which method I prefer most.

I might end up too lazy to reboot into bootcamp everytime I want to do something on windows, or vm might be unusable with my system specs, I will see.

It will be on an ssd, a recent one faster than the one my macbook shipped with, but not by that much.

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Answer 10

Sep 11, 2020 3:28 PM in response to GGarrett2

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.

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Answer 11

GGarrett2 Author

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Sep 11, 2020 3:43 PM in response to BobTheFisherman

I don't want to make a thing out of this but I knew bootcamp would be best performance, I mentioned it in my first post, I wanted to know if there would be any difference between 2 and 3, and I linked to a page from parallels that highlighted their feature that you can run it in 3 different ways, also in my first post.

I'm not saying you're wrong or right, I don't know, but others in this thread have said there may or will be a difference, which is what I believe, or parallels wouldn't publish pages like that contrasting the 3 ways to run it, but I may be wrong about that.

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Answer 12

Sep 11, 2020 3:44 PM in response to GGarrett2

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.