RE: [Dev-C++] Optimized memory allocation

[Ioannis V. <iv...@em...>]

Bug fix:
=20

-----Original Message-----
From: dev...@li...
[mailto:dev...@li...] On Behalf Of Ioannis
Vranos
Sent: Friday, June 20, 2003 5:48 AM
To: 'C++'
Subject: RE: [Dev-C++] Optimized memory allocation


 =3D=3D>  new whatever[SIZE]  should be equivalent to
malloc(SIZE*sizeof(whatever))  in terms of speed, where whatever is a =
POD
type.
=20
 But better use an std::vector:
=20
=20
#include <vector>
=20
// ...
=20
using std::vector;
=20
// ...
=20
vector<class_type> array(48);
=20
// ...
array[0]=3D ...
=20
=20
=20
=20
=20
Ioannis Vranos

* Programming pages:  <http://www.noicys.freeurl.com/>
http://www.noicys.freeurl.com
* Alternative URL 1:  <http://run.to/noicys> http://run.to/noicys
* Alternative URL 2:  <http://www.noicys.cjb.net/> =
http://www.noicys.cjb.net

=20
=20
=20

-----Original Message-----
From: dev...@li...
[mailto:dev...@li...] On Behalf Of Shane =
Bryldt
Sent: Friday, June 20, 2003 3:39 AM
To: C++
Subject: [Dev-C++] Optimized memory allocation


Hello,
=20
    I have recently been attempting to find ways to speed up the process =
of
loading 48k records from a MySQL SELECT statement, which has a 32 char
primary key.  One of the more intensive processes involved is calling =
"new"
to create a new object 48k times.  In standard C, I would =
malloc(RowCount *
sizeof(class_type)), and using pointer math, simply iterate whenever I
needed a new structure.  With C++, a call to new is required for
construction purposes.  Is there an optimized method wherein I can =
allocate
a dynamic number to be preallocated more efficiently all at once in one
call?
    I have considered using "new class_type[RowCount]()" to allocate an
array (haven't tried to see if that would actually work), but I was
wondering if there was a more efficient means to preallocate objects.
=20
Thanks,
    -Shane