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Free Parallel Programming Training

 Intel is offering FREE online training, in collaboration with Colfax.

The upcoming training will start September 9th and it includes free 3-week remote access to a Intel® Xeon® and Intel® Xeon Phi™ server.

Another series of training will start October 13th.

For more details and registration, please check: http://colfaxresearch.com/how-series/

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floating point exception solving a non-symmetric matrix

The floating point exception occurs when solving the attached non-symmetric matrix.

1 line: n

2nd line: index base (i.e. 0 based)

3rd line: nz

followed by all nonzeros in coordinate (i.e. triplet) format

Major version: 11
Minor version: 1
Update version: 1
Product status:  Product
Build: n20131010
Processor optimization: Intel(R) Advanced Vector Extensions (Intel(R) AVX) Enabled Processor




Why no simple linear equation solver?

I looked in the INTEL MATH KERNEL library, and could not find a routine that just solves


where A is an N by N matrix, and X and B are vectors of length N.

They throw a lot of confusing **** at you, when you just want to solve a basic problem,

and dont have a system with special characteristics, like SPARSE, Band, Hermitian, etc.


So its impossible to just find a basic routine to give you a quick answer.

Or if its there, they sure don't bother to tell you where - - - -


Can each thread on Xeon Phi be given private data areas in the offload model


I want to calculate a  Jacobian matrix, which is a sum of 960 (to be simple) 3x3 matrices  by distributing the calculations of these 3x3 matrices to a Xeon Phi card. The calculation of the 3x3 matrices uses a third party library whose subroutines use an interger vector not only for the storage of parameter values but also to write and read intermidiate results. It is therefore necessary for each task to have this integer vector protected from other tasks. Can this be obtained on the physical core level or even for each thread (each Xeon Phi has 60x4=240 threads. 

mpirun with bad hostname hangs with [ssh] <defunct> until Enter is pressed

We have been experiencing hangs with our MPI-based application and our investigation led us to observing the following behaviour of mpirun:

mpirun -n 1 -host <good_hostname> hostname works as expected

mpirun -n 1 -host <bad_hostname> hostname hangs, during which ps shows: 

Vtune amplxe-gui freezes, asks to send report/terminate


I am trying to profile a Fortran program with the vtune amplifier. I created a report using 

amplxe-cl -collect general-exploration -result-dir vtune_results_smaller exec_name exec_001.rc

where 'exec_001.rc' is a config file read by exec_name. The report collection seemed to go fine, but when I tried to view the results using 

Multithreading when called by C++, not when called by R

Hi everyone, I have been struggling with a problem for quite some time, and I would greatly appreciate your input.

I have a program that uses Intel MKL's dgemm function many times.  In fact, to demonstrate my problem, I used exactly the same code as is in this dgemm tutorial:  https://software.intel.com/en-us/node/429920.

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