Questions tagged [openmpi]

Open MPI is an open source implementation of the Message Passing Interface, a library for distributed memory parallel programming.

The Open MPI Project is an open-source implementation of the Message Passing Interface, a standardized and portable message-passing system designed to leverage to computational power of massively parallel, distributed memory computers.

Message passing is one of the distributed memory models most often used, with MPI being the most used message passing API, offering two types of communication between processes: point-to-point or collective. MPI can run in distributed and shared memory architectures.

An application using MPI consists usually of multiple simultaneously running processes, normally on different CPUs, which are able to communicate with each other. Normally, this type of application is programmed using the SPMD model. Nevertheless, most MPI implementations also support the MPMD model.

More information about the MPI standard may be found on the official MPI Forum website, in the official documentation, and in the Open MPI documentation.

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OpenMPI node isn't recognizing the IP of another node in the cluster

I am very new to OpenMPI/Parallel Computing in general. I have been following this guide here on how to do it, and I have gone through literally 99% of the guide without a problem, it’s this final test that has been giving me issue, and I haven’t…
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Why mpicxx is uble to compile cpp code includes boost library?

I am trying to compile a code in a Linux-based cluster with open PBS scheduler using the following command /home/debamalya/cpp/cpp_libraries/open_mpi/bin/mpicxx -I/home/debamalya/cpp/cpp_libraries/boost_1_81_0/…
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Update OpenMPI version 2.1.1 to version 4.1.4 on Ubuntu 18.04

To run a specific set of code I require the latest version of ompi. To do this I followed this video: https://youtu.be/QIMAu_o_5V8 All seems to work well however, when I restart my laptop and check the version of ompi (ompi_info), it still states…
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What is the final value printed if the the program below is executed with 5 MPI processes?

What is the final value printed if the the program below is executed with 5 MPI processes? #include #include #include int main (int argc, char** argv) { int value=0; int size, rank; MPI_Status s; …
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Trying to wrap my head around some nonblocking mpi behaviour

So I've been trying some things in MPI to get a feel for it and I've produced some results that I can't explain by combing through the documentation. I'm using open mpi. #include #include #include #define PROBLEMSIZE 41…
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How do I correctly set the "send counts" and "displacement" arguments in MPI_scatterv?

I am trying to split up a 2 dimensional array's rows between "n" processes using MPI_Scatterv. The two arguments that are stopping me is "send_counts" and "displacements". I know the textbook definition of what these arrays do, but I need a way to…
comfychair
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how can i solve an error with MPI_Ssend with producer and consumer problem

So i need to solve the problem of multiple producer and consumers using open mpi. The compiler says that there are an error in MPI_Ssend, but where? (id_buffer == 4) void funcion_productor(int productor_i) { int b = 4; for ( unsigned int i= 0…
Yunhao
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open mpi not enough slots available

I'm running a simple hello world program written in C on mpi and the problem I'm having is that i can't seem to execute 10 processes for this simple program. #include #include "mpi.h" int main(int argc, char *argv[]) { int rank;…
Maxxx
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cygwin mpicxx not found

I'm trying to use mpicxx with cygwin. I've installed all openmpi packages available but when typing mpicxx still get a "command not found". I looked into the /usr/bin folder and mpicxx is missing, while C and fortran versions are there. Any possible…
tidus95
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why bash shell does not make any difference after executed?

I'm working a small project which needs using OpenMPI to make "mpicc" work. I made a file make_cmd: #!/bin/bash module load OpenMPI However, after executing ./make_cmd, I was told: mpicc: command not found But if I just type on the command line:…
user419050
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mpi4py does not speed up embarrisingly parallelizable code

I am trying to diagonalize a large number of totally independent matrix computations using numpy.linalg, and openmpi/mpi4py on a 6-core intel xeon machine. When running with N processes, each matrix computation seems to take N times longer so that…
DrewP
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Figuring out the number of processors for using openmpi

I have compiled a weather forecasting software with openmpi in double precision on Ubuntu 14.04 and Intel ifort compiler. However I am not able to figure out few issues. I need to figure out the number of processors I need to send to mpirun. This…
gansub
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Perl: How to add an interrupt handler so one can control a code executed by mpirun via system()?

We use a cluster with Perceus (warewulf) software to do some computing. This software package has wwmpirun program (a Perl script) to prepare a hostfile and execute mpirun: # ... system("$mpirun -hostfile $tmp_hostfile -np $mpirun_np @ARGV"); #…
Andrei
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What is different from MPI_SEND with rank in a loop and sending without loop in MPI

i am trying these logic code, and i do not know what is different between them. I am trying to use MPI_Send() and MPI_Recv() in my program. As i understand, in MPI, processess communicate via their ranks of each processor, and tags of each message.…
November Rain
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Replace MPICH Installation by OpenMPI

I currently have MPICH (release 3.1.4) installed on my machine (running Mac OS X 10.10.5). I would like to remove it and install OpenMPI instead but could find no instructions online on how to uninstall MPICH. Is it sufficient to simply delete…
Janosh
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