I have gone through How does a PE file get mapped into memory?, this is not what i am asking for.
I want to know which sections (data, text, code, ...) of a PE file are always completely loaded into memory by the loader no matter whatever the condition is?
As per my understanding, none of the sections (code,data,resources,text,...) are always loaded completely, they are loaded as and when needed, page by page. If few pages of code (in the middle or at the end), are not required to process user's request then these pages will not always get loaded.
I have tried making exe files with lots of code with/without resources both of which are not used at all, but, every time the exe loads into memory, it takes more memory than the file size. (I might have been looking at the wrong column of Memory in Task Manager)
Matt Pietrek writes here
It's important to note that PE files are not just mapped into memory
as a single memory-mapped file. Instead, the Windows loader looks at
the PE file and decides what portions of the file to map in.
and
A module in memory represents all the code, data, and resources from
an executable file that is needed by a process. Other parts of a PE
file may be read, but not mapped in (for instance, relocations). Some
parts may not be mapped in at all, for example, when debug information
is placed at the end of the file.
In a nutshell,
1- There is an exe of size 1 MB and available memory (physical + virtual) is less than 1 MB, is it consistent that loader will always refuse to load because available memory is less than the size of file?
2- If an exe of size 1 MB takes 2 MB memory when loaded (starts running first line of user code) while available memory (physical + virtual) is 1.5 MB, is it consistent that loader will always refuse to load because there is not enough memory?
3- There is an exe of size 50 MB (lots of code, data and resources) but it requires 500 KB to run the first line of user code, is it consistent that this exe will always run first line of code if available memory (physical + virtual) is 500 KB atleast?
See Question&Answers more detail:
os 
