# Error allocating memory

**URL:** <https://calculix.discourse.group/t/error-allocating-memory/1429>\
**Category:** Uncategorized\
**Created:** [January 3, 2023, 10:46am UTC](https://calculix.discourse.group/t/error-allocating-memory/1429 "2023-01-03T10:46:40Z")\
**Posts on this page:** 1\
**Showing post:** 6

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**Author:** ![JuanP74](https://avatars.discourse-cdn.com/v4/letter/j/b5a626/32.png) [@JuanP74](https://calculix.discourse.group/u/JuanP74)\
**Post date:** [January 3, 2023, 8:50pm UTC](https://calculix.discourse.group/t/error-allocating-memory/1429/6 "2023-01-03T20:50:59Z")

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check out this thread, I think I got it from here…but not sure (mine is v2.19 for windows)…[CalculiX i8 and mingw - #7 by jbr](https://calculix.discourse.group/t/calculix-i8-and-mingw/134/7)

anyway 64GB of ram should be enough for about 2 Million equations (dofs) according to the manual, so keep it in mind.

from the installation guide [http://www.dhondt.de/ccx\_2.20.README.INSTALL](http://www.dhondt.de/ccx_2.20.README.INSTALL) :

* * *

USING CALCULIX with 8 byte per integer

* * *

This may be necessary for really big models. Right now, there is a file  
Makefile\_i8 showing you how it works. The integers in the FORTRAN files must  
be compiled with the option -fdefault-integer-8 (for the GNU compiler). This  
tells the compiler to consider all integers in the FORTRAN files as  
8-byte integers. For the C-files, the flag -DLONGLONG must be added to the  
CFLAGS. Right now, the CalculiX distribution assumes that you also generate  
a integer_8 version of ARPACK (use the above FORTRAN flag) and an  
integer_8 version of PARDISO (of course only if you use any if these, i.e.  
if you have the flags -DPARDISO and -DARPACK in your Makefile). The  
SPOOLES distribution, however, is assumed to be an integer _4, since it  
is not known that an integer_8 version of SPOOLES has already been made.

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