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Parallel Scalable Burrows-Wheeler Transformation (BWT) Using Intel® Threading Building Blocks and OpenMP Libraries

by Arthur V. Ratz

This article is a practical guide on using Intel® Threading Building Blocks (TBB) and OpenMP libraries for C++ based on the example of delivering parallel scalable code that implements Burrows-Wheeler Transformation (BWT) algorithm.

Allocating Memory in C/C++: How to Avoid Memory Mismatched Allocation/Deallocation Issues Detected by Intel® Inspector XE for Visual Studio 2015

by Arthur V. Ratz

This tip/trick introduces the basic ideas on how to avoid memory mismatched allocation/deallocation issues detected by Intel® Inspector XE for Visual Studio 2015

Using Fortran DO CONCURRENT for Accelerator Offload

by Intel

The purpose of this article is to assess its strengths and weaknesses for heterogeneous parallelism.

The Present and Future of the OpenMP API Specification

by Intel

How the Gold Standard Parallel Programming Language Has Improved with Each New Version

Latest Articles

The Case for OpenMP Target Offloading

by Intel

This article will take a closer look at the advantages and disadvantages of the Fortran DO CONCURRENT statement and the OpenMP target constructs with respect to accelerator offload.

Using Fortran DO CONCURRENT for Accelerator Offload

by Intel

The purpose of this article is to assess its strengths and weaknesses for heterogeneous parallelism.

Solving Linear Systems Using oneMKL and OpenMP Target Offloading

by Henry A Gabb, Nawal Copty

Accelerate Linear Algebra Computations with Standard, Open Approaches

Solving Heterogeneous Programming Challenges with Fortran and OpenMP

by Shiquan Su PhD, Ron_Green, Barbara Perz, Pamela Harrison

Expressing Heterogeneous Parallelism Using Open, Standard Programming Languages

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OpenMP

Parallel Scalable Burrows-Wheeler Transformation (BWT) Using Intel® Threading Building Blocks and OpenMP Libraries

2 May 2017 by Arthur V. Ratz

This article is a practical guide on using Intel® Threading Building Blocks (TBB) and OpenMP libraries for C++ based on the example of delivering parallel scalable code that implements Burrows-Wheeler Transformation (BWT) algorithm.

Allocating Memory in C/C++: How to Avoid Memory Mismatched Allocation/Deallocation Issues Detected by Intel® Inspector XE for Visual Studio 2015

1 May 2017 by Arthur V. Ratz

This tip/trick introduces the basic ideas on how to avoid memory mismatched allocation/deallocation issues detected by Intel® Inspector XE for Visual Studio 2015

OpenMP code stalling

19 Dec 2014 by bling

Your for loop is probably too fine grained. Try breaking the work up into chunks.void convolve_inner(Bitmap &src,Kernel &kernel, Bitmap &dst, int low, int high){ // process one stripe or band of image data. for(int y = low; y

Need help parallelizing the C++ code using openmp

9 May 2016 by Patrice T

Before using threads, you should start by optimizing your code.Just a few optimizations:- Everywhere, you use convertToString(0), replace with '0'. Same for convertToString(1) and '1'.Wait ...you have 3 nested loops for(int r=0;r

Please I need clarification with some sections of game of life code with openmp written in C

13 Feb 2022 by Rick York

1. The macro substitution makes the expression look like this : BOARD(ingrid, inorth, jwest) -> ((ingrid)[NC*(inorth)+(iwest)]) In this the parenthesis are just enclosing the token, or ingrid in this case, to make it a singular expression. 2....

Using Fortran DO CONCURRENT for Accelerator Offload

15 Dec 2023 by Intel

The purpose of this article is to assess its strengths and weaknesses for heterogeneous parallelism.

Open MP process time

16 Jan 2012 by alianzalima1978

hi everyone!i'm working with a simple image process program using open mp,but can't get make my program faster as it's supposed to be.the process time of the code bellow was 0.5secs.but with the open mp line commented out, it was only 0.1secs.i can't see what is going on.please...

Open MP process time

15 Jan 2012 by Sergey Alexandrovich Kryukov

Did you gain 5 times in performance? This is better result as I would expect. How could you expect more if you only have 2 cores? Do you think parallel processing is the miracle, can draw power from nowhere? :-)—SA

Open MP process time

15 Jan 2012 by Jochen Arndt

The inner loop var x is shared by default. You should make it private:#pragma omp parallel for private(x)This should boost performance. But I'm not sure if this is all.

Open MP process time

16 Jan 2012 by Stefan_Lang

simple image process program using open mpThat is the first mistake: Multithreading is never simple!The second problem is memory access: I don't know how clever OMP goes about it, but I doubt it will recognize that for each y you access values from a very specific range of memory, and...

convert image to grayscale using C++ openMP (simple)

22 Jan 2013 by H.Brydon

I am not sure if you are having trouble with the coding part or the parallelization part. In the code you have given here, you could linearize the code by commenting out the "omp_set_num_threads()" and "#pragma omp parallel for" statements to debug the program. These directives take (supposedly)...

convert image to grayscale using C++ openMP (simple)

22 Jan 2013 by Maxim Kartavenkov

Hello,Here is the brief description of what you need:#include #pragma comment(lib,"gdiplus.lib")// Initialize GDI+ULONG _token;Gdiplus::GdiplusStartupInput _input;Gdiplus::GdiplusStartup(&_token, &_input, NULL);// Shutdown GDI+Gdiplus::GdiplusShutdown(_token);//...

OpenMP code stalling

19 Dec 2014 by BupeChombaDerrick

Hello everyone, I have a computer vision algorithm in which the convolution algorithm must be run in parallel on multicore processors using openMP. The code is of the form as shown below. void convolve(Bitmap &src,Kernel &kernel, Bitmap &dst) #pragma omp parallel for for(int...

Getting error when trying to enable openmp on android with NDK

30 Mar 2015 by BupeChombaDerrick

Hello everyone, I'am getting this error when compiling with android native developer kit (NDK) aarch64-linux-android-g++.exe: error: libgomp.spec: No such file or directory. I have specified the following flags in the android.mk file LOCAL_CFLAGS += -fopenmpLOCAL_LDFLAGS +=...

OpenMP on for() loops

19 Apr 2015 by Amos Chew

I'm using OpenMP to parallelise a couple of for() loops but I'm not sure which "#pragma" command is the right one to use. These situations that I've faced which hopefully possible to parallelise. Really need your help in this.Situation 1 - Is it possible to use "#pragma omp parallel for"...

How can I modify my sequential code into parallel using openmp?

16 Jul 2016 by KarstenK

Making code parallel isnt always the solution, because it also makes overhead for that. Your primary task should be finding the slow parts of code and redesign them.As I see you often writing in the writeToAnswerFile file. That looks like a bottleneck. I would try to store that information...

Is image processing with openmp possible

23 Jan 2017 by Afzaal Ahmad Zeeshan

Just use OpenCV, it will take care of parallelism for you. Most of the code in OpenCV already makes a good use of OpenMP so if your machine supports these features, they will be utilized heavily by the framework itself. Read these threads for answer, Does OpenCV functions really use OpenMP -...

multi-threading

The Present and Future of the OpenMP API Specification

17 Apr 2017 by Intel

How the Gold Standard Parallel Programming Language Has Improved with Each New Version

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Happy 20th Birthday, OpenMP

26 May 2017 by Intel

Making Parallel Programming Accessible to C/C++ and Fortran Programmers―and Providing a Software Path to Exascale Computation

parallel-processing

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OpenMP Is Turning 20!

31 Aug 2017 by Intel

Making Parallel Programming Accessible to C/C++ and Fortran Programmers

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How to make openmp thread sleep

16 Oct 2017 by Member 13466456

I am currently working on a project to design Airport with OOP. I am using c++. I have a main Airport object in my program which has RequestLanding() function which assigns the runway number on which plane can land. This function returns one of the two enums- Hold or Proceed to indicate whether...

How to make openmp thread sleep

16 Oct 2017 by KarstenK

I would solve this problem NOT with some waiting function, but a semaphore solution. Semaphore are resources which allowing some designated access and so fitting best for your probelm. For learning on semaphores is a short explanation from Microsoft and also some deeper insights. This link may...

How to configure clang under visual studio (windows) to compile openmp that targets GPU

8 May 2021 by Member 4315396

Hi, I'm struggling to find informations on how to target GPUs with clang under Visual Studio. My code compiles, it just doesn't create multiple threads nor omp_is_initial_device() returns a value different than zero. Thanks in advance for any...

How to configure clang under visual studio (windows) to compile openmp that targets GPU

8 May 2021 by KarstenK

when the code compiles the primary settings should be fine, so I suggest that you check the rror code of omp_is_initial_device() to find the details. If it doesnt help you should try to contact some developers who really are in touch with that...

Please I need clarification with some sections of game of life code with openmp written in C

13 Feb 2022 by UT7

Hello everyone, please I need clarification about some sections of John Conway's Game of life code written in C that is parallelized with OpenMp. The code is below, please if any of the questions is too elementary please don't be offended. ...

Solving Linear Systems Using oneMKL and OpenMP Target Offloading

11 May 2023 by Henry A Gabb, Nawal Copty

Accelerate Linear Algebra Computations with Standard, Open Approaches

The Case for OpenMP Target Offloading

18 Dec 2023 by Intel

This article will take a closer look at the advantages and disadvantages of the Fortran DO CONCURRENT statement and the OpenMP target constructs with respect to accelerator offload.

The Concave Hull of a Set of Points

16 Aug 2017 by Alasdair Craig

A C++ implementation of a published algorithm for computing the concave hull using a k-nearest neighbour approach.

Solving ordinary differential equations with OpenCL in C++

26 Jul 2012 by headmyshoulder, Denis Demidov

This article shows how ordinary differential equations can be solved with OpenCL. In detail it shows how odeint - a C++ library for ordinary differential equations - can be adapted to work with VexCL - a library for OpenCL. The resulting performance is studied on two examples.

convert image to grayscale using C++ openMP (simple)

22 Jan 2013 by mr_lawzy

This is the first time that I use C++. A part of my project is to convert a given image (rgb) of any type (ex:bmp) to grayscale using c++ OpenMp.I did some google search online and found on code project a function that does the conversion in c++ and openMP as follows: ...

Solving Heterogeneous Programming Challenges with Fortran and OpenMP

8 May 2023 by Shiquan Su PhD, Ron_Green, Barbara Perz, Pamela Harrison

Expressing Heterogeneous Parallelism Using Open, Standard Programming Languages

Is image processing with openmp possible

23 Jan 2017 by Member 12963359

can i use openmp for image processing so that after increasing number of threads the image processing can do in fast wayWhat I have tried:after increasing threads no performance increase done

multi-threading

Segmentation Fault (Core Dumped) Problem : Whenever I Search For Keywords In A .Raw File.

24 Mar 2014 by Rahul Mohanan

/* Program for Bad Character Heuristic of Boyer Moore String Matching Algorithm */ # include # include # include #include #include #include #include # define NO_OF_CHARS 256using namespace std;// An...

Is setting omp_set_num_threads(1) equivalent to linear programming?

8 May 2016 by Member 12509578

Is setting omp_set_num_threads(1) equivalent to linear programming if i have some parallel for loop?And what is the use of omp_set_dynamic(0);What I have tried:I am tring to run nested for loops and had the above query.

Use OpenMP or MPI for laptop Intel Core!

10 Sep 2013 by kiet.heros

I have laptop with Intel Core I5-2430M.I don't know to call that is Simultaneous multithreading or multi-core.And I'm also ambiguous between using OPENMP or MPI to program parallel on my laptop.Do anyone explain to me ? Thanks !

Need help parallelizing the C++ code using openmp

10 May 2016 by Member 12509578

I am new to openmp. If anyone could suggest some more changes to get this program work faster, it would be very helpful. In this program values.txt is a file containing 60 crore ( 600 millions) lines with each line having a 32 bit permutation of 16 0's and 16 1's. Explanation-It would be...

How can I modify my sequential code into parallel using openmp?

16 Jul 2016 by Member 11465955

Hi, I have written a program, which works like 24 game puzzle i.e. from the given integer set and a target value, I list all the possible mathematical expressions to evaluate that target value.Now, I want to modify this code using openMP in order to speedup the program. So, can anyone help me...