Moving to D

[Long Chang]

2011/1/6 Walter Bright <newshound2 at digitalmars.com>

> bearophile wrote:
>
>> Adrian Mercieca:
>>
>>  How does D square up, performance-wise, to C and C++ ? Has anyone got any
>>> benchmark figures?
>>>
>>
>> DMD has an old back-end, it doesn't use SSE (or AVX) registers yet (64 bit
>> version will use 8 or more SSE registers), and sometimes it's slower for
>> integer programs too.
>>
>
> The benchmarks you posted where it was supposedly slower in integer math
> turned out to be mistaken.
>
>
>  I've seen DMD programs slow down if you nest two
>> foreach inside each other. There is a collection of different slow
>> microbenchmarks.
>>
>> But LDC1 is able to run D1 code that looks like C about equally fast as C
>> or
>> sometimes a bit faster.
>>
>> DMD2 uses thread local memory on default that in theory slows code down a
>> bit
>> if you use global data, but I have never seen a benchmark that shows this
>> slowdown clearly (an there is __gshared too, but sometimes it seems a
>> placebo).
>>
>> If you use higher level constructs your program will often go slower.
>>
>
> Rubbish. The higher level constructs are "lowered" into the equivalent low
> level constructs.
>
>
>
>  Often one of the most important things for speed is memory management, D
>> encourages to heap allocate a lot (class instances are usually on the
>> heap),
>> and this is very bad for performance,
>>
>
> That is not necessarily true. Using the gc can often result in higher
> performance than explicit allocation, for various subtle reasons. And saying
> it is "very bad" is just wrong.
>
>
>
>  also because the built-in GC doesn't
>> have an Eden generation managed as a stack. So if you want more
>> performance
>> you must program like in Pascal/Ada, stack-allocating a lot, or using
>> memory
>> pools, etc. It's a lot a matter of self-discipline while you program.
>>
>
> This is quite wrong.
>

I using D for 3 years . I am not in newsgroup because my English is very
pool .
D is excellent , I try it with Libevent,  Libev,  pcre, sqlite,  c-ares,
dwt, and a lot other amazing Lib. It work great with C-lib .   I enjoy it so
much .
My work is a web developer, I also try use D in web field ,  It not result
well .

Adam D. Ruppe post some interesting cod in here , And I find a lot people
try in web field. for example: (mango, https://github.com/temiy/daedalus,
Sendero  ... )   , But in the end I had to say, most D project is dying .

D like a beautiful girl friends,  You play with her can have a lot of fun.
But she is be scared to make promisee ,   you can't count your life on it.
she is not a good potential marriage .  her life is still in mess, and day
after day she is more smart but not become more mature.    so if you want do
some serious work ,  You'd better choose another language.  if you just wan
fun , D is a good  companion .
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