14-Feb-2013 03:22, Ivan Kazmenko пишет:
Hi!
I'm learning to use D collections properly, and I'm looking for a sorted
data structure with logarithmic access time (i.e., a binary search tree
will do, but a hash table would not help). As far as I can see,
std.container.RedBlackTree is exactly what I need. However, I am not
sure if I use it as intended as its performance seems inferior to a C++
STL solution (e.g., std::set).
To be more specific, right now I wonder what is the best (or intended)
way to store an object in the RedBlackTree: should it be a class
reference, or a struct (passed by value), or something quirkier like an
integer pointing into an array or a simple pointer. The rest of my
program suggested to use structs, but the whole thing turned out to be
rather slow, and the profiler told me that these structs are being
copied around much more than I anticipated.
And so I wrote a minimalistic test program to check the number of copy
(postblit) constructor calls. Here is the D version:
[snip]
And the results are:
D2 (DMD 2.059, -O): 11,389,556
I'd add :
-release -inline
or it may not inline away temporary copies.
--
Dmitry Olshansky
