Load balance file

TRACE distributes the blocks to the processes of a parallel computation depending on their size. You can specify your own distribution by providing a load balance file. It consists of one line for each process following the scheme:

<rank> <nBlocks>[:<nThreads>] <block1> [<block2> ...]

Parameters

rank	Rank of process (starting with 0)
nBlocks	Number of blocks assigned to the process
nThreads	Number of threads spawned by the process
blockN	Block number of blocks on the process (starting with 0)

A load balance file can be generated using PREP with the command:

PREP -clb -cgns <filename> -np <nProcs>

where <filename> is the name of the CGNS-file and <nProcs> is the number of processors in the parallel calculation. The result is an ASCII file BALANCE_<nProcs>PROC. PREP uses the same mechanism as TRACE's automatic load balancing.

Example

0 2:5 0 5
1 3   1 4 7
2 3   2 3 6

In this example, a configuration consisting of 8 blocks is distributed to 3 processes. Blocks 0 and 5 are computed by process 0 using 5 threads, blocks 1, 4, 7 are computed by process 1 and blocks 2, 3, 6 are computed by process 2.