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Re: Stack is slow than heap?

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"Nephi Immortal"  wrote in message 
news:2ec220c4-7264-4980-8802-57ad7c3c66eb@s7g2000yqa.googlegroups.com...
>
>On Nov 8, 5:00 am, Nick Keighley <nick_keighley_nos...@hotmail.com>
>wrote:
>> Include your question in the body of your post
>>
>> "Stack is slow than heap"
>>
>> maybe. It all depends on the implementaion. I'd expect access time to
>> be very similar. Allocation/release is a little slower for heap
>> (dynamic memory) than stack (automatic memory).
>
>Heap is slow unless you allocate and deallocate heap many times.
>Heap is pretty fast if you allocate one time prior reaching main
>function and deallocate one time after exiting main function.  If you
>insist, you have to allocate and deallocate very often, you will
>implement your own memory pool to speed up performance.

Heap and stack are usually accessing the same memory. So access times are 
not different. Only allocation/release times are different. 
Allocating/releasing stack is usually somewhat faster.

> ...

>>
>> >         After you write a function, do you prefer to store one buffer 
>> > to hold
>> > 1,024 bytes or 4,096 bytes?
>>
>> I've never been given this option!. I'd choose the smaller number if
>> 1024 bytes were enough for my function. Wouldn't it be a good idea to
>> pick the correct number?
>>
>> > Should 4,096 bytes be sufficient to hold
>> > buffer or small array in stack?
>>
>> this is a nonsense question. What is the buffer for?
>
>If you have multiple buffers outside function, you will need to
>create one temporary buffer inside function and copy all multiple
>buffers into one buffer before one buffer outputs to the screen like
>printf() or cout << … << endl;
>I guess temporary buffer should hold sufficient 4,096 bytes or less.

It depends on what you want to do. If you want to output one line of text, 
then a buffer of about 100 characters may be sufficient. If you want to 
refresh a whole screen in one go, then it depends on the screen resolution 
and the possible values of one cell. A screen with a resolution of about 200 
x 100 and about 200 possible values per cell will need already a buffer of 
at about 20000 bytes.

> ... 

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Stack is slow than heap? Nephi Immortal <immortalnephi@gmail.com> - 2011-11-07 08:27 -0800
  Re: Stack is slow than heap? Victor Bazarov <v.bazarov@comcast.invalid> - 2011-11-07 11:47 -0500
    Re: Stack is slow than heap? BGB <cr88192@hotmail.com> - 2011-11-07 15:28 -0700
      Re: Stack is slow than heap? Nephi Immortal <immortalnephi@gmail.com> - 2011-11-08 07:35 -0800
        Re: Stack is slow than heap? "io_x" <a@b.c.invalid> - 2011-11-08 18:17 +0100
          Re: Stack is slow than heap? Nephi Immortal <immortalnephi@gmail.com> - 2011-11-08 11:39 -0800
            Re: Stack is slow than heap? "io_x" <a@b.c.invalid> - 2011-11-09 03:42 +0100
              Re: Stack is slow than heap? "io_x" <a@b.c.invalid> - 2011-11-09 03:55 +0100
                Re: Stack is slow than heap? "io_x" <a@b.c.invalid> - 2011-11-09 03:58 +0100
      Re: Stack is slow than heap? Cholo Lennon <chololennon@hotmail.com> - 2011-11-08 17:52 -0300
        Re: Stack is slow than heap? BGB <cr88192@hotmail.com> - 2011-11-09 00:09 -0700
          Re: Stack is slow than heap? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-11-09 17:33 +0000
            Re: Stack is slow than heap? Juha Nieminen <nospam@thanks.invalid> - 2011-11-10 06:44 +0000
              Re: Stack is slow than heap? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-11-10 20:14 +0000
                Re: Stack is slow than heap? Juha Nieminen <nospam@thanks.invalid> - 2011-11-10 21:01 +0000
                Re: Stack is slow than heap? Cholo Lennon <chololennon@hotmail.com> - 2011-11-10 18:55 -0300
                Re: Stack is slow than heap? Juha Nieminen <nospam@thanks.invalid> - 2011-11-11 07:37 +0000
                Re: Stack is slow than heap? gwowen <gwowen@gmail.com> - 2011-11-11 02:18 -0800
                Re: Stack is slow than heap? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-11-10 22:34 +0000
          Re: Stack is slow than heap? Paavo Helde <myfirstname@osa.pri.ee> - 2011-11-09 14:38 -0600
            Re: Stack is slow than heap? BGB <cr88192@hotmail.com> - 2011-11-09 15:30 -0700
  Re: Stack is slow than heap? "io_x" <a@b.c.invalid> - 2011-11-07 19:32 +0100
    Re: Stack is slow than heap? "io_x" <a@b.c.invalid> - 2011-11-07 19:50 +0100
      Re: Stack is slow than heap? Edek <edek.pienkowski@gmail.com> - 2011-11-07 20:10 +0100
  Re: Stack is slow than heap? Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-11-08 03:00 -0800
    Re: Stack is slow than heap? Nephi Immortal <immortalnephi@gmail.com> - 2011-11-08 07:45 -0800
      Re: Stack is slow than heap? "Fred Zwarts \(KVI\)" <F.Zwarts@KVI.nl> - 2011-11-08 17:28 +0100
      Re: Stack is slow than heap? Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-11-09 02:20 -0800
        Re: Stack is slow than heap? Werner <werasm@gmail.com> - 2011-11-09 03:03 -0800
          Re: Stack is slow than heap? Dombo <dombo@disposable.invalid> - 2011-11-09 20:16 +0100
            Re: Stack is slow than heap? Richard Damon <news.x.richarddamon@xoxy.net> - 2011-11-09 23:35 -0500

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