On 2009-06-08 15:55:26 +0200, Sean Kelly <[email protected]> said:
Fawzi Mohamed wrote:
On 2009-06-07 10:47:47 +0200, Christian Kamm
<[email protected]> said:
bearophile wrote:
The following code even crashes LDC during the compilation, I'll ask in
the LDC channel:<
The good ChristianK has already added it:
http://www.dsource.org/projects/ldc/ticket/320
And thankfully Frits van Bommel has already fixed it: it consumes about 40kb
of heap memory at runtime now.
This seems to be because we don't use the _d_arrayappend functions at all
but emit a _d_arraysetlength instead. What's the memory growing behavior of
that function? Should this be considered a bug?
I would say that setlength should not allocate extra space, because one
should trust that the user knows his needs
char[] x;
x.length = 100; // setlength allocates memory
I thought it was clear that I meant that (apart some rounding up done
by the gc), the allocation created by x.length should no allocate
*extra* space (meaning more that needed), because it is quite clear
that the user wants that much space, and the likelihood that he doesn't
really know, and some extra space would be good is not so high.
Thus adding space would most likely be wasted.
If the user appends to an array, and reallocation is needed on the
other hand, the probability that that array will be appended again is
much higher, so it makes sense to allocate some extra space. This makes
continuously appending to an array perform O(log(N)) reallocations.
In any case I fixed the newCapacity function in tango, with one of my
guesses for a good function.
But if anybody comes with some benchmarks that suggest and improvement
I will gladly do it.
Fawzi
