Myoxocephalus
February 9th, 2011, 12:53 PM
Hi!
I have a quick question regarding MPI and sending of information to nodes. My code, somewhat simplified, does this:
MPI_reduce(...);
if (myrank == 0){
do a lot of stuff, and find value for variable x_var;
if (x_var < limit){
x_step += dx;
}
}
Now, this works fine for on node. But, when I use several nodes, the value of x_step is only changed on node with rank 0. I want node 0 to do this job, and then update x_step on ALL nodes. I don't know if that was clear or not. What I'm looking for is probably something av a reveres of MPI_reduce; somthing sends a variable to all nodes so that everyone has the same.
Can anyone help me out? Thanks a lot!
Best regards,
Myoxocephalus
I have a quick question regarding MPI and sending of information to nodes. My code, somewhat simplified, does this:
MPI_reduce(...);
if (myrank == 0){
do a lot of stuff, and find value for variable x_var;
if (x_var < limit){
x_step += dx;
}
}
Now, this works fine for on node. But, when I use several nodes, the value of x_step is only changed on node with rank 0. I want node 0 to do this job, and then update x_step on ALL nodes. I don't know if that was clear or not. What I'm looking for is probably something av a reveres of MPI_reduce; somthing sends a variable to all nodes so that everyone has the same.
Can anyone help me out? Thanks a lot!
Best regards,
Myoxocephalus