Initial and Max Memory Windows 10 VM

[fwiler]

New to KVM so perhaps I'm not familiar with the nomenclature compared to hyper-v

 

If I use initial memory 2048 and max memory 4096, it doesn't dynamically adjust which I assumed it would.

 

Looking at performance under task manager and you can see allocation is very strange.

With 2048-4096 it shows 4.0GB memory with 82-85% used on a fresh install (with drivers installed), and will reach 96% as soon as any activity starts.  Will reach 100% and things slow down.

i.e. 3.6/4.0 GB used, even though if you add up all processes, it doesn't come anywhere close to 3.6GB used.

So although it reports 4096, it is acting as 2048 is the limit.

 

With Initial and max at 4096-4096 it shows about 30 percent used on a fresh install and memory looks fine as applications load.  Never reaching even 50%.

 

[JonathanM]

Do some google searches about KVM memory ballooning and see if you get an idea for why you are seeing what you are.

 

For the scenario you are describing, I'd leave RAM at 2048 and call it a day. The host can make much better use of the the RAM than the guest to make the guest run smoothly. Keep in mind any RAM allocated to the guest is locked away from the host, which could have used it to cache I/O and make the rest of the guest emulation better. Only give the guest the minimum necessary CPU and RAM, so the emulated motherboard and other resources are as fast as possible.