• Nick Sabalausky (27/28) Apr 12 2012 Consider this program:
• Nick Sabalausky (7/8) Apr 12 2012 Actually, that junk doesn't matter, I found a way to put it without gett...
• Manfred Nowak (5/6) Apr 12 2012 Your guess is wrong. process monitor from sysinternals reveals, that

"Nick Sabalausky" <SeeWebsiteToContactMe semitwist.com> writes:

Consider this program:

// blank.d
void main() {
    while(true) {} // Poor man's sleep ;)
}

dmd blank.d

On WinXP 32-bit DMD 2.058, if I run that, task manager tells me it's using 
8816k of memory.

*Note: I'm not complaining.*

I just wanted to ask if anyone knows what that overhead is primarily from?

Just from druntime/phobos being statically linked? OS process overhead? Some 
DLLs that are implicitly used? (But I assume DLLs aren't counted in that 
memory usage figure...) Etc... I don't think it's from the raw exe file 
itself being loaded into mem, because that's only 143k.

As a frame of reference, if I change "true" to "1" and compile with DMC 
(instead of DMD), then it only uses 1265k ram. (The exe file is smaller too, 
but *that* I'm sure is just because of phobos/druntime being statically 
linked.)

The reason I'm asking is I'm making a few minor edits to my "Have Your 
Efficiency, and Flexibility Too" article, and I'm tempted to breifly point 
out that the 10% decrease in memory usage with the "handcrafted version" is 
better than it sounds because most of that 10MB ram is just overhead. But 
saying that D programs have 8-9MB runtime overhead probably sounds very bad, 
so I'm not sure I want to do it if I can't provide a (breif) "Don't worry! 
Because..."

(Although I may still just skip the whole mention altogether and just leave 
it at "10% decrease in memory - and now on to the next section" and not even 
worry about it. Whatever. In any case, I am at least curious.)

"Nick Sabalausky" <SeeWebsiteToContactMe semitwist.com> writes:

"Nick Sabalausky" <SeeWebsiteToContactMe semitwist.com> wrote in message 
news:jm63tu$27uq$1 digitalmars.com...
 The reason I'm asking is[...]

Actually, that junk doesn't matter, I found a way to put it without getting 
that detailed and derailed.

But I am curious what the memory overhead is from. My guess would be that 
it's just memory used by misc parts of the statically-linked 
phobos/druntime, but I don't actually know.

Manfred Nowak <svv1999 hotmail.com> writes:

Nick Sabalausky wrote:

 But I am curious what the memory overhead is from. My guess

Your guess is wrong. process monitor from sysinternals reveals, that 
several windows system dll's are loaded under the process number 
belonging to that loop.

-manfred