Most performant way of converting int to string

[Daniel Kozák via Digitalmars-d-learn]

V Tue, 22 Dec 2015 09:43:00 -0800
"H. S. Teoh via Digitalmars-d-learn"
<digitalmars-d-learn at puremagic.com> napsáno:

> On Tue, Dec 22, 2015 at 05:23:11PM +0000, Andrew Chapman via
> Digitalmars-d-learn wrote: [...]
> >         for({int i; i = 0;} i < num; i++) {
> >                 //string s = to!string(i);
> >                 Customer c = Customer(i, "Customer", "99998888", i
> > * 2); string result = objS.serialize(c);
> >         }
> > 
> > If I uncomment the "string s" line I'm seeing a 20% increase in
> > running time, which given what's going on the rest of the code is
> > quite surprising.  I've tried compiling with both dmd and ldc2 -
> > it's the same under both.  
> [...]
> 
> I wonder if the slowdown is caused by GC collection cycles (because
> calling to!string will allocate, and here you're making a very large
> number of small allocations, which is known to cause GC performance
> issues).
> 
> Try inserting this before the loop:
> 
> 	import core.memory;
> 	GC.disable();
> 
> Does this make a difference in the running time?
> 
> 
> T
> 
This would  not help. It would probably be worse.