[SOLVED] Do threads help virtual machines host and guest performance?

Satearn

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I have done some benchmarking with my i5-8400. I run some scripts on the guest machines, and simultaneously run tests on host machine.

And test results are crystal clear, increasing the cores for guest machine in virtual box instantly decreases host CPU performance.

Results on App Timer:

Host 1 core + guest 5 cores = Host running very slow

Host 4 cores + guest 2 cores = Host running near normal speed

Now the cores obviously make tons of difference, but what about threads?

Would a 6/12 i7-8700k outperform my 6/6 ?

Or do I need to go thread ripper with maybe 12 cores or more?

 
Solution
VirtualBox is just for tinkering/playing with various OS's , so I'd not be making conclusions on how well a VM does with/without hyperthreading when you overallocate cores in a Type 2 VM when strangling the host OS.....

Time to jump to to a TYpe1 Hypervisor such as ProxMox, ESXi, KVM, HyperV, etc....much more appropriate for actual work.
Well, threads are essentially virtual or fake cores, all in all it allows for a real physical, in a crude way to say' perform 2 tasks altogether provided theres resources to do so.

however lets say a task is so optimized that i can fully use a core entirely, then theres no resources left for running a 2nd lane in that core, and having more threads is useless. In short however, its speculated that a 6/12 can provide around ish 20/30% performance boost in multi-threaded tasks over a 6/6.
 

Satearn

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Interesting, I heard that Intel has more instructions per second, so in my case, do you think an i7-8770k might perform as well or better than an Ryzen 2700x even if it has 6/12 vs Ryzen 8/16?

In other words, would the 6 i7-8700k have more power than the Ryzen 8 cores?

So maybe 6 intel cores = 8 ryzen core power?
 
Thats a complicated question, its quite known at this point that intel has better performance for single tasks, gaming and such, but ryzen have been performing better in multi-tasking and all exactly for that reason, it has more real cores as an attractive over intel's sheer firepower.

so, while im not so sure how your situation applies, what i can tell is that if whatever application you use benefits with more cores operating, then although the ryzen is slower core x core, it has more cores so it will win for that matter, now if you need more firepower and less core, lets say... in gaming to being with, intel will do better.

EDIT: i'm sorta, just sorta guessing the ryzen will do better, as its performance isnt really so horrible lower than that of the 8700, and with those extra cores it could prove better.

 

Satearn

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I don't game at all, ever. I don't even have or need a graphics card, this is all for work.

So say you put the 2 side by side.

Would 6 Intel i7-8700k cores have more power than 8 Ryzen 2700x cores?

 


What do you need to run?
Do you just need the host to be responsive?
You can put the whole virtual machine on idle priority from task manager,that way the host will always be responsive with the task in the guest suffering performance.
Virtualbox allows you to set a limit on how much in % of the real cores the virtual cores are allowed to use so you can dial in the balance of performance that you want to have.
 
VirtualBox is just for tinkering/playing with various OS's , so I'd not be making conclusions on how well a VM does with/without hyperthreading when you overallocate cores in a Type 2 VM when strangling the host OS.....

Time to jump to to a TYpe1 Hypervisor such as ProxMox, ESXi, KVM, HyperV, etc....much more appropriate for actual work.
 
Solution