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Re: Why is java consumer/producer so much faster than C++

Cross-posted to 2 groups.

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In comp.lang.c++ Melzzzzz <mel@zzzzz.com> wrote:
> I think that pressure on condition variable is greater with non
> dynamic allocation, therefore it is slower.

That sentence doesn't make any kind of sense.

> I don't think it's
>> physically possible for 'new int' to be faster than using ints by
>> value under any possible circumstance, even if we assumed a highly
>> optimized version of 'new' that does magic under the hood to be 10
>> times faster than the regular 'new'.
> 
> That's because new is very fast and don;t take much time of program
> in this example.

'new' is a very slow operation in C++, and even if it weren't, it just
can't be faster than using an integer by value. It's physically impossible.
(The pointer that points to the allocated int is also an integral value at
the low level, so by allocating something dynamically you are only adding
to the amount of values being handled, and the overall complexity of the
program.)

Can you give any scenario where handling pointers would be faster than
handling ints?

>> 'new' is slow, especially when compared to java's.
> 
> In this example new takes very little time.

You are executing tens of thousands of 'new's. That is slow.

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Thread

Why is java consumer/producer so much faster than C++ Melzzzzz <mel@zzzzz.com> - 2012-07-22 23:59 +0200
  Re: Why is java consumer/producer so much faster than C++ Joshua Maurice <joshuamaurice@gmail.com> - 2012-07-22 15:42 -0700
    Re: Why is java consumer/producer so much faster than C++ Melzzzzz <mel@zzzzz.com> - 2012-07-23 01:28 +0200
      Re: Why is java consumer/producer so much faster than C++ Luca Risolia <luca.risolia@studio.unibo.it> - 2012-07-23 02:03 +0200
        Re: Why is java consumer/producer so much faster than C++ Melzzzzz <mel@zzzzz.com> - 2012-07-23 12:17 +0200
          Re: Why is java consumer/producer so much faster than C++ Luca Risolia <luca.risolia@studio.unibo.it> - 2012-07-24 00:33 +0200
  Re: Why is java consumer/producer so much faster than C++ Juha Nieminen <nospam@thanks.invalid> - 2012-07-23 06:37 +0000
    Re: Why is java consumer/producer so much faster than C++ Melzzzzz <mel@zzzzz.com> - 2012-07-23 12:33 +0200
      Re: Why is java consumer/producer so much faster than C++ Juha Nieminen <nospam@thanks.invalid> - 2012-07-23 11:46 +0000
        Re: Why is java consumer/producer so much faster than C++ Melzzzzz <mel@zzzzz.com> - 2012-07-23 15:33 +0200
  Re: Why is java consumer/producer so much faster than C++ Dombo <dombo@disposable.invalid> - 2012-07-23 22:57 +0200
    Re: Why is java consumer/producer so much faster than C++ Joshua Maurice <joshuamaurice@gmail.com> - 2012-07-23 21:54 -0700
      Re: Why is java consumer/producer so much faster than C++ Jorgen Grahn <grahn+nntp@snipabacken.se> - 2012-07-24 12:50 +0000
  Re: Why is java consumer/producer so much faster than C++ Ricardo Nabinger Sanchez <rnsanchez@wait4.org> - 2012-08-14 22:48 +0000

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