mpi Questions
2
Solved
I use a MPI (mpi4py) script (on a single node), which works with a very large object. In order to let all processes have access to the object, I distribute it through comm.bcast(). This copies the ...
Billet asked 9/9, 2015 at 16:43
1
I am a computer science student and this season we have a course in MPI programming in C language. I don't have enough hard disk space to install visual studio on my computer and I have installed c...
Jiminez asked 10/1, 2018 at 18:13
3
Solved
I have the code snippet below in C++ which basically calculates the pi using classic monte carlo technic.
srand48((unsigned)time(0) + my_rank);
for(int i = 0 ; i < part_points; i++)
{
doub...
Rankle asked 14/2, 2012 at 21:27
2
Solved
I am trying to get a hybrid OpenMP / MPI job to run so that OpenMP threads are separated by core (only one thread per core). I have seen other answers which use numa-ctl and bash scripts to set env...
1
Solved
I'm trying to run a c++ code (BCparallel.cpp) using MPI; compiling the code with:
mpic++ BCparallel.cpp -o BCparallel
is well succeed, but when I pass the line
mpiexec -np 4 BCparallel file.t...
Hibbler asked 24/11, 2017 at 11:16
2
I come from a sort of HPC background and I am just starting to learn about machine learning in general and TensorFlow in particular. I was initially surprised to find out that distributed TensorFlo...
Klaraklarika asked 18/9, 2017 at 15:8
1
How do I find the number of cores available to MPI(4PY)?
Motivation
My Python program spawns MPI instances hierarchically.
The first spawn always happens and creates 4 instances. It doesn't m...
Import asked 13/11, 2017 at 10:29
0
I am trying to start a ipyparallel cluster using MPI.
The ipcluster_config has following lines modified as such:
c.MPILauncher.mpi_cmd = ['mpiexec']
c.MPIControllerLauncher.controller_args = ['-...
Bolter asked 12/11, 2017 at 5:26
1
So I have a trobule with gmsh.
Direct execution works fine:
!gmsh -3 -algo meshadapt tmp_0.geo -o SFM.msh
While execution from code fails:
try:
out = subprocess.check_output(
["gmsh", "gmsh ...
Acupuncture asked 15/9, 2017 at 13:44
6
Solved
I have a C++ code that can be compiled with MPI support depending on a
certain preprocessor flag; missing the appropriate flag, the sources
compile to a non-parallel version.
I would like to setup...
2
Solved
I'm parallelizing an already existent application that uses gTest with MPI. In MPI programs, the first thing to do is to initialize the environment with a call to
MPI_Init( int *argc, char ***arg...
Anecdotal asked 13/5, 2013 at 16:16
1
So I'm a noob when it comes to this sort of stuff.
I'm struggling to compile a climate model on macOS and I've boiled it down to what is going on here:
#define _GNU_SOURCE
#include <stdio.h&...
1
Solved
In MPI gather and scatter there is two counts for send and receive. I checked the docs and found out that both should have the same value.
Ex:- In MPI_Gather() both send_count and receive_count s...
B asked 16/7, 2017 at 20:35
1
Solved
I have an MPI program which oversubscribes/overcommits its processors. That is: there are many more processes than processors.
Only a few of these processes are active at a given time, though, so ...
Pickering asked 6/5, 2016 at 18:3
1
Solved
I am running in a cluster. I tried to run my executable with 4 different forms:
In serial, with
myexec
This starts giving output in stdout right away, as expected.
In serial, redirecting stdou...
2
Solved
I don't understand how the environment is set on compute nodes when running with MPI under a scheduler.
I do:
mpirun -np 1 --hostfile ./hostfile foo.sh
with foo.sh:
#!/usr/bin/env zsh
echo $L...
Kudu asked 27/5, 2015 at 9:5
1
What is an efficient way to send/receive bits from bitset class without conversion. Is it possible to use MPI_BYTE?
If so, what to define as container for the array that is going to hold the bits?...
Palmore asked 6/4, 2017 at 18:54
2
Solved
I've been using MPI_Scatter / MPI_Gather for a variety of parallel computations. One thing I've noticed is that MPI_Barrier() is often called to synchronize processors, akin to the OpenMP bar...
Halfandhalf asked 15/5, 2017 at 19:23
3
Solved
I'm not sure when I have to use different numbers for the tag field in MPI send, receive calls. I've read this, but I can't understand it.
Sometimes there are cases when A might have to send man...
Hornbill asked 13/7, 2015 at 14:52
2
Solved
My program is well-suited for MPI. Each CPU does its own, specific (sophisticated) job, produces a single double, and then I use an MPI_Reduce to multiply the result from every CPU.
But I repeat t...
4
Solved
I am working on a tool to model wave energy converters, where I need to couple two software packages to each other. One program is written in Fortran, the other one in C++. I need to send informati...
6
Solved
Which profiler do you use for Fortran code base with MPI in it? gprof doesn't seem to be working correctly. Sun Studio Analyzer only returns the timings for the C/C++ system calls and none of the f...
1
Solved
I read that is recommended to use the MPI module rather than include mpif.h file. However, I get the following error
Error: There is no specific subroutine for the generic ‘mpi_comm_split’
w...
2
Solved
The displs argument from MPI_Scatterv() function is said to be an "integer array (of length group size). Entry i specifies the displacement (relative to sendbuf from which to take the outgoing data...
Dimitri asked 24/12, 2016 at 15:17
3
I have two GCC compilers installed on a Linux (CentOS) machine. The old version of GCC (4.4.7) is in the default folder (came with CentOS) and the newer one that I intend to use is in /usr/local/gc...
© 2022 - 2024 — McMap. All rights reserved.