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digitalmars.D.learn - Size of Compiled Program

reply Martin Tschierschke <mt smartdolphin.de> writes:
When I was writing a small speed test - D versus Ruby,
calculating the first n prime numbers, I realized, that for small 
n
Ruby may be faster, than compiling and executing with D.
But for n = 1,000,000 D outperforms Ruby by app. 10x.

Looking at the size of my prime executable, it was around 800 kB 
with DMD
and even with optimization and "gdc -Os" > 1 MB.
Why is such a short program resulting in a so big binary?
-----------------------------------------------------------------------------
import std.stdio;
import std.conv;
int[] prime; // Dynamic Array of Prime

// Ist n durch eine der zahlen in prime teilbar?
bool teilbar(int n){
         for(auto i=0; prime[i]*prime[i]<=n ; i++){
                 if (n%prime[i]==0) return true;
         }
         return false;

}

void main(string[] args)   // first parameter number of primes to 
calculate
{
         auto anzahl = 10; // default
         prime ~= 2;       // first element of the array
         if(args.length==2){
                 anzahl = to!int(args[1]);}
         auto pruefe=1;
         while (prime.length <= anzahl){
                 pruefe+=2;
                 if(!teilbar(pruefe)){
                         write(" ",pruefe);
                         prime ~= pruefe; // append the array
                 }
         }

         write("\n das wars...:",prime.length);
}
Jan 04 2016
next sibling parent reply Basile B. <b2.temp gmx.com> writes:
On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
wrote:

 When I was writing a small speed test - D versus Ruby,
 calculating the first n prime numbers, I realized, that for 
 small n
 Ruby may be faster, than compiling and executing with D.
 But for n = 1,000,000 D outperforms Ruby by app. 10x.

 Looking at the size of my prime executable, it was around 800 
 kB with DMD
 and even with optimization and "gdc -Os" > 1 MB.
 Why is such a short program resulting in a so big binary?


You have the runtime and phobos compiled with your program. But 
also:
- if debug info are generated this increases the size.
- if bounds checking is turned off there is some code generated 
for each array operation
- if contracts are not off there is a lot of assertion that will 
be generated

see also some clues here:
http://forum.dlang.org/post/mailman.20.1441974998.22025.digitalmars-d-learn puremagic.com
Jan 04 2016
parent Martin Tschierschke <mt smartdolphin.de> writes:
On Monday, 4 January 2016 at 14:01:18 UTC, Basile B. wrote:

 On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
 wrote:


[...]

 - if debug info are generated this increases the size.
 - if bounds checking is turned off there is some code generated 
 for each array operation
 - if contracts are not off there is a lot of assertion that 
 will be generated

 see also some clues here:
 http://forum.dlang.org/post/mailman.20.1441974998.22025.digitalmars-d-learn puremagic.com


Ah, thank you for that Link!
Jan 04 2016
prev sibling next sibling parent reply Marc =?UTF-8?B?U2Now7x0eg==?= <schuetzm gmx.net> writes:
On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
wrote:

 When I was writing a small speed test - D versus Ruby,
 calculating the first n prime numbers, I realized, that for 
 small n
 Ruby may be faster, than compiling and executing with D.
 But for n = 1,000,000 D outperforms Ruby by app. 10x.

 Looking at the size of my prime executable, it was around 800 
 kB with DMD
 and even with optimization and "gdc -Os" > 1 MB.
 Why is such a short program resulting in a so big binary?


That's probably basic these compilers statically link the runtime 
(and standard?) libraries by default. Compiling your program with 
`ldc2 -O3`, I get a binary of 28K, and stripping gets it down to 
17K.
Jan 04 2016
parent Martin Tschierschke <mt smartdolphin.de> writes:
On Monday, 4 January 2016 at 14:16:54 UTC, Marc Schütz wrote:

 On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
 wrote:

 When I was writing a small speed test - D versus Ruby,
 calculating the first n prime numbers, I realized, that for 
 small n
 Ruby may be faster, than compiling and executing with D.
 But for n = 1,000,000 D outperforms Ruby by app. 10x.

 Looking at the size of my prime executable, it was around 800 
 kB with DMD
 and even with optimization and "gdc -Os" > 1 MB.
 Why is such a short program resulting in a so big binary?


 That's probably basic these compilers statically link the 
 runtime (and standard?) libraries by default. Compiling your 
 program with `ldc2 -O3`, I get a binary of 28K, and stripping 
 gets it down to 17K.


Ok, I will try ldc2, too.
Jan 04 2016
prev sibling parent reply Adam D. Ruppe <destructionator gmail.com> writes:
On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
wrote:

 When I was writing a small speed test - D versus Ruby


The smallest possible ruby program has about ~5 MB of 
dependencies, outside the operating system (the ruby runtime 
itself).

The D program has none. It carries its runtime with it, which 
makes the executable a bit larger to compensate but helps 
compatibility with other computers because the user doesn't have 
to hunt down obscure D runtime packages.
Jan 04 2016
parent reply Martin Tschierschke <mt smartdolphin.de> writes:
On Monday, 4 January 2016 at 14:51:59 UTC, Adam D. Ruppe wrote:

 On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
 wrote:

 When I was writing a small speed test - D versus Ruby


 The smallest possible ruby program has about ~5 MB of 
 dependencies, outside the operating system (the ruby runtime 
 itself).

 The D program has none. It carries its runtime with it, which 
 makes the executable a bit larger to compensate but helps 
 compatibility with other computers because the user doesn't 
 have to hunt down obscure D runtime packages.


Oh, thats interesting. When I tried to run the compiled "prime" 
on my notebook,
with the "same" Ubuntu release, I got an error, may be its 32 not 
64 Bit?
Any hint?
Jan 04 2016
next sibling parent Adam D. Ruppe <destructionator gmail.com> writes:
On Monday, 4 January 2016 at 16:56:15 UTC, Martin Tschierschke

 with the "same" Ubuntu release, I got an error, may be its 32 
 not 64 Bit?
 Any hint?


Yeah, probably.
Jan 04 2016
prev sibling parent Jacob Carlborg <doob me.com> writes:
On 2016-01-04 17:56, Martin Tschierschke wrote:


 Oh, thats interesting. When I tried to run the compiled "prime" on my
 notebook,
 with the "same" Ubuntu release, I got an error, may be its 32 not 64 Bit?
 Any hint?


You can run the "file" command to see which architecture an executable 
is built for.

-- 
/Jacob Carlborg
Jan 05 2016