On Monday, 16 April 2012 at 22:58:08 UTC, Timon Gehr wrote:
On 04/17/2012 12:24 AM, ReneSac wrote:
Windows.
DMC runtime !
DMC = Digital Mars Compiler? Does Mingw/GDC uses that? I think
that both, g++ and GDC compiled binaries, use the mingw runtime,
but I'm not sure also.
No. They are not the same. The performance difference is
probably explained by the dmc runtime vs. glibc difference,
because your biased results are not reproducible on a linux
system where glibc is used for both versions.
Ok, I will benchmark on linux latter.
This is a fallacy. Benchmarks can only compare implementations,
not languages. Furthermore, it is usually the case that
benchmarks that have surprising results don't measure what they
intend to measure. Your program is apparently rather I/O bound.
Yeah, I'm comparing the implementation, and I made it clear that
it may be the GDC front-end that may be the "bottleneck".
And I don't think it is I/O bound. It is only around 10MB/s,
whereas my HD can do ~100MB/s. Furthermore, on files more
compressible, where the speed was higher, the difference between
D and C++ was higher too. And if is in fact I/O bound, then D is
MORE than 50% slower than C++.
The difference is likely because of differences in external C
libraries.
Both, the D and C++ versions, use C's stdio library. What is the
difference?
