leaving MS for ubuntu-linux

I’m about to convert to Linux world, private and my company, after making a study for a year, i still hesitate, do to the fact, that i dont possesses the knowledge. i’m running ubuntu 20 on several laptops and thats so so, because it is hard to learn and make new SW installments. next step is to setup my servers, so what SW to use, i’m leaning towards ubuntu again? PLM system? what about open PLM? the ideal during my trancition would to run double OS, but i still havent figured out, how to get rid off, the one i dont want to keep.can i run server with ubuntu, and still have access from MS, just storage/folders? I have tried to find a normal person in south west of Sweden who can help me at site, but the few i have found want a fortune to help!

ram – Find exact physical memory usage in Ubuntu/Linux

(I’m new to Linux)

Say I’ve 1300 MB memory, on a Ubuntu machine. OS and other default programs consumes 300 MB memory and 1000 MB is free for my own applications.

I installed my application and I could configure it to use 700 MB memory, when the application starts.

However I couldn’t verify its actual memory usage. Even I disabled swap space.

The “VIRT” value shows a huge value and “RES“, “SHR“, “%MEM” shows very less value.

It is difficult to find actual physical memory usage, similar to “Resource monitor” in Windows, which will say my application is using 700 MB memory.

Is there any way to find actual physical memory in Ubuntu/Linux ?