Don't worry imekon, you're definately not the first person to make the mistake you're making, and you certainly will not be the last. The explanation below was written about Gnome, but it applies here too. What you need to understand is that most of
the 20MB you're seeing belongs to the .NET Framework itself (not the application), which falls into the Share part (i.e. if you run a bunch of managed apps at the same time they can share that memory and it only counts once for the whole lot of them, not once
Understanding Memory usage in GNOME.
Miguel de Icaza (email@example.com)
People usually look at the memory sizes for the processes and misinterpret the information. This is a common mistake.
When talking about memory usage and the reports you get from the operating system, you need to keep in mind the following terms and what they mean:
SIZE This is the address space seen by the process. If the process maps 65 megs of memory, the address space of the process will be reported as 65 megs of memory.
Even if only 100k of memory are actually used.
This bit of information is not usually very useful and this is what most people believe is the actual memory usage of a program: it is not.
RSS This is the "Resident Set Size". This is the amount of memory actually resident on memory. This is a better computation of what is actually loaded in memory.
This does not include any piece of code that have been "swapped out".
So, for example, if you have a program that uses 100k of memory and the operating system discards or swaps 40k of memory, the RSS will be 60k.
The RSS includes both the memory which is unique to this process and the memory shared with other processes. In most modern Unix systems, a large part of this accounts for the memory used by shared libraries. So it usually includes the ammount of memory that is used by other processes for the code that is shared: The libc is usually taken into account.
GNOME uses many shared libraries (this makes the applications share more memory).
SHARE This is the amount of memory from the RSS that is shared with other applications.
So, the actual memory used uniquely by an application is RSS - SHARE.