topic Fortran Parallel in Software Archive

Fortran Parallel

alirezayaseri — Sat, 25 Feb 2012 16:47:44 GMT

I will appreciate if anyone can help me through this problem :

I want to use two prallel systems for solving mentioned code in below, because i have not enough physical memory to solve the problem.

program Console3

implicit none

! Variables
integer, allocatable :: A(:,:)

allocate(A(50000,50000))
end program Console3

Fortran Parallel

Steven_L_Intel1 — Sat, 25 Feb 2012 22:03:44 GMT

First, I want to comment that this question would be better put in one of the Fortran forums, since "Intel Paralllel Studio" does not support Fortran. (Intel Parallel Studio XE does.)

Parallelization and memory usage are really two different things. The array size you have there would fit in a 32-bit application, however - it is just under 1GB. But if you had larger arrays, or more than one, you would need the 64-bit environment. Physical memory is not the issue either - virtual memory is.

So far you have not shown anything that would benefit from parallelization. Please note that parallelization would not, on its own, allow you to have larger problem sizes.

If you need more help, please ask in one of our Fortran forums. We have one for Windows and one for Linux/Mac.

Fortran Parallel

SergeyKostrov — Sun, 26 Feb 2012 01:26:04 GMT

>>...
>>integer, allocatable :: A(:,:)
>>
>>allocate(A(50000,50000))
>>...

Here is an evaluation ofhow much memoryis needed:

50,000 * 50,000 * 4 ( integer / 4 bytes )= 10,000,000,000 = 9.31GB

Here are some conclusions:

-Consider a 64-bit platform(s)

- It is impossible to allocate 9.31GB of memory on a 32-bit Windows platform(s) without AWE
( even if a size of VM is 16GB, for example.There is a limit for an applicationand it is2GB)

- It is possible to allocate memory blocks greater than4GBon a 32-bit Windowsplatform(s) with AWE

AWE - Address Windowing Extensions ( Microsoft's technology ).
Please take a look for more informationat MSDN's topic 'Platform SDK: Memory Management'

Could you provide more technical details on what you need to compute?

Best regards,
Sergey