[Nek5000-users] 'COMMON' block issue

[nek5000-users at lists.mcs.anl.gov]

To me it looks like the number of elements are to large to fit on just 32 ranks. Increase lpmin!

On 7 Nov 2018, at 17:11, nek5000-users--- via Nek5000-users <nek5000-users at lists.mcs.anl.gov <mailto:nek5000-users at lists.mcs.anl.gov> > wrote:

When you define your object in the common block, do you define it so that it stays the same size regardless of how many threads you use?  Presumably, it should look something like this:
common /mydata/ data(lx1*ly1*lz1*lelt)

So that when you double the number of threads, you halve the value of lelt

On Mon, Oct 8, 2018 at 8:25 PM <nek5000-users at lists.mcs.anl.gov <mailto:nek5000-users at lists.mcs.anl.gov> > wrote:
Dear Nek users,

 
Currently, I am working on a simulation with a decent size (11760 * 12 elements) employing ‘lpmin = 32’. When I compile, I received an error saying: “relocation overflows omitted from the output”.  I googled this error and it turned out this error comes from the ‘COMMON’ block;  Static data, such as COMMON variables, and all of the code together is still limited to 2GB under any mcmodel.  The suggested solution is to  move the data out of a COMMON block and into a module and make the data allocatable. 

The most straightforward way to avoid this would be increase the ‘lpmin’ (for example if lpmin = 64, then it works), but this does not solve this issue, which is a big constraint. I am wondering has anyone has run into this and got any experience in solving it?

 
Thanks a lot in advance

_______________________________________________
Nek5000-users mailing list
Nek5000-users at lists.mcs.anl.gov <mailto:Nek5000-users at lists.mcs.anl.gov> 
https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users

_______________________________________________

Nek5000-users mailing list

Nek5000-users at lists.mcs.anl.gov <mailto:Nek5000-users at lists.mcs.anl.gov> 

https://lists.mcs.anl.gov/mailman/listinfo/nek5000-users
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/nek5000-users/attachments/20181107/66eb972d/attachment.html>