Hello everybody, I am trying to distribute over a BLACS grid a square complex (double precision) matrix making use of the Cpzgemr2d function. This global matrix resides on a single "master" node and I need to distribute it over my grid as preliminary step of a linear system solution calculation. Everything works fine if I try to run my code with matrix of size of about 2GB or smaller, making use of various BLACS grids (2x2,3x3,4x4, etc...) with row/column block size equal to 64. However, increasing the matrix size for example to 4 GB, for the same grid and data block configuration, I receive an "xxmr2d:out of memory" error message after a call to Cpzgemr2d, which is not able to complete the matrix distribution procedure. Memory availability on my test machine is quite large (more than 40 GB per MPI task) and I am only allocating the mermory required for global and local matrix data blocks, so I guess that memory itself should not be the cause of my problem.
Is there any size limit for the above data distribution procedure? My test machine is a UNIX cluster and I am working with MKL Scalapack.
Many thanks in advance for your help!