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Subject: Re: [OMPI users] calculation progress status
From: Andreas Schäfer (gentryx_at_[hidden])
Date: 2013-10-21 10:19:22


the solution depends on the details of your code. Will all clients
send their progress updates simultaneously? Are you planning for few
or many nodes?

For few nodes and non-simultaneous updates you could loop on the root
while receiving from MPI_ANY. Clients could send out their updates via

If you're expecting many nodes, this 1-n schema will eventually
overwhelm the root node. In that case MPI_Gather() or MPI_Reduce()
will perform better. But those require all nodes to participate.

Things get complicated if you want non-simultaneous updates from many


On 15:07 Mon 21 Oct , MM wrote:
> Hello,
> I have a n-variable function optimization task that I programmed with a
> scatter, each mpi process evaluates my function in part of the space, then
> a reduce to get the maximum at the root process. Most wall time is spent in
> the function evaluations done inside every mpi process.
> I would like to report to the root process some progress indicator, ie 40%
> done so far and so on...
> What is the customary solution?
> Thanks
> MM

> _______________________________________________
> users mailing list
> users_at_[hidden]

Andreas Schäfer
HPC and Grid Computing
Chair of Computer Science 3
Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany
+49 9131 85-27910
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