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POMatrix multiplication of 10000 X 10000
 

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  1. POMatrix multiplication of 10000 X 10000
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    <p>I need to perform a Matrix multiplication of two matrices of dimension 10,000 X 10,000, each element is randomly generated from range 1 to 10,000. I need to do it with threads (25 threads) and without threads and compare the time. I am using a simple Matrix multiplication algorithm O(n^3). The program without threads has been executing forever (more than a day) and the threaded version aborts when i try to run it. It works fine for 1000 X 1000 Matrix</p> <p>I compiled it using CC prog.cc -lpthread -lposix4 on my university server Here's the non-threaded version</p> <p>/* Compiler: Unix Server </p> <p>This program performs matrix multiplication of two 10000*10000 matrices without threads The purpose of the program is to demonstrate the performance gain using threads against not using threads to perform the same computation on different data. */</p> <pre><code>#include &lt;pthread.h&gt; #include &lt;iostream.h&gt; #include &lt;semaphore.h&gt; #include &lt;unistd.h&gt; #include&lt;math.h&gt; int main() { double **A;//Matrix A double **B;//Matrix B double **C;//Output Matrix C const int MATRIX_DIMENSION = 5000; //Assign Matrix A first dimension //----------------------------------------------------------- A = new double*[MATRIX_DIMENSION]; //Assign second dimension for(int i = 0; i &lt; MATRIX_DIMENSION; i++) { A[i] = new double[MATRIX_DIMENSION]; } //Assign Matrix B first dimension B = new double*[MATRIX_DIMENSION]; //Assign second dimension for(int i = 0; i &lt; MATRIX_DIMENSION; i++) { B[i] = new double[MATRIX_DIMENSION]; } //Assign Matrix C first dimension C = new double*[MATRIX_DIMENSION]; //Assign second dimension for(int i = 0; i &lt; MATRIX_DIMENSION; i++) { C[i] = new double[MATRIX_DIMENSION]; } //----------------------------------------------------------- //Generate random numbers for matrices A and B and assign C to 0 for(int i=0;i&lt;MATRIX_DIMENSION;i++) { for(int j=0;j&lt;MATRIX_DIMENSION;j++) { A[i][j] = rand() % 10000; B[i][j] = rand() % 10000; C[i][j] = 0; // initialize C to zero } } //----------------------------------------------------------- //Do the matrix multiplication for(int i=0;i&lt;MATRIX_DIMENSION;i++) { for(int j=0 ;j&lt;MATRIX_DIMENSION; j++) { for(int k=0;k&lt;MATRIX_DIMENSION;k++) { C[i][j]+=A[i][k]*B[k][j]; } } } //----------------------------------------------------------- //delete the dynamic memory of A for (int i = 0; i &lt; MATRIX_DIMENSION; i++) { delete[] A[i]; } delete[] A; //delete the dynamic memory of B for (int i = 0; i &lt; MATRIX_DIMENSION; i++) { delete[] B[i]; } delete[] B; //delete the dynamic memory of C for (int i = 0; i &lt; MATRIX_DIMENSION; i++) { delete[] C[i]; } delete[] C; //----------------------------------------------------------- return(0); } </code></pre> <p>Here's the threaded version /* Name: Compiler: Unix Server </p> <p>This program performs matrix multiplication of two 10000*10000 matrices without threads The purpose of the program is to demonstrate the performance gain using threads against not using threads to perform the same computation on different data. */</p> <pre><code>#include &lt;pthread.h&gt; #include &lt;iostream.h&gt; #include &lt;semaphore.h&gt; #include &lt;unistd.h&gt; #include&lt;math.h&gt; //Global variables double **A;//Matrix A double **B;//Matrix B double **C;//Output Matrix C const int MATRIX_DIMENSION = 10000; //We need a 10000 X 10000 Matrix const int NUM_THREADS = 25; // One thread completes 1/25th of the work const int THREAD_DIMENSION = MATRIX_DIMENSION / NUM_THREADS; //Array that each thread will operate on pthread_t * thread[NUM_THREADS]; /*************************************************************************** Function that does matrix multiplication of 1/25th of the whole matrix, The division is done by dividing the Matrix into row's all 1/25 of the total matrix Each row of Matrix A operates on all the columns of Matrix B to get corresponding elements of Matrix C Parameter : arg, this is used as and index for which part of the Matrix this particular thread operates on Return type: void ****************************************************************************/ void *MatrixMul (void * arg) { int index; index = (int) arg; int operation_Lower_Limit = ((index+1) * THREAD_DIMENSION) - THREAD_DIMENSION ; //Multiplication starting row int operation_Upper_Limit = ((index+1) * THREAD_DIMENSION) - 1; //Multiplication ending row for(int i=operation_Lower_Limit;i&lt;=operation_Upper_Limit;i++) //only 1/25th of Matrix A is used { for(int j=0 ;j&lt;MATRIX_DIMENSION; j++) // The whole B matrix is used { for(int k=0;k&lt;MATRIX_DIMENSION;k++) { C[i][j]+=A[i][k]*B[k][j]; } } } return NULL; } int main() { srand(time(0)); //Assign memory for threads for(int i=0;i &lt; NUM_THREADS;i++) { thread[i] = new pthread_t; } //Assign Matrix A first dimension //----------------------------------------------------------- A = new double*[MATRIX_DIMENSION]; //Assign second dimension for(int i = 0; i &lt; MATRIX_DIMENSION; i++) { A[i] = new double[MATRIX_DIMENSION]; } //Assign Matrix B first dimension B = new double*[MATRIX_DIMENSION]; //Assign second dimension for(int i = 0; i &lt; MATRIX_DIMENSION; i++) { B[i] = new double[MATRIX_DIMENSION]; } //Assign Matrix C first dimension C = new double*[MATRIX_DIMENSION]; //Assign second dimension for(int i = 0; i &lt; MATRIX_DIMENSION; i++) { C[i] = new double[MATRIX_DIMENSION]; } //----------------------------------------------------------- //Generate random numbers for matrices A and B and assign C to 0 for(int i=0;i&lt;MATRIX_DIMENSION;i++) { for(int j=0;j&lt;MATRIX_DIMENSION;j++) { A[i][j] = rand() % 10000; B[i][j] = rand() % 10000; C[i][j] = 0; // initialize C to zero } } //----------------------------------------------------------- //Do the matrix multiplication for(int i=0;i&lt;NUM_THREADS;i++) { pthread_create( thread[ i ], NULL, (MatrixMul), (void *) (i) ); } //wait for all the threads to complete execution for(int i=0;i&lt;NUM_THREADS;i++) { pthread_join(*thread[i],NULL); } //----------------------------------------------------------- //delete the dynamic memory of A for (int i = 0; i &lt; MATRIX_DIMENSION; i++) { delete[] A[i]; } delete[] A; //delete the dynamic memory of B for (int i = 0; i &lt; MATRIX_DIMENSION; i++) { delete[] B[i]; } delete[] B; //delete the dynamic memory of C for (int i = 0; i &lt; MATRIX_DIMENSION; i++) { delete[] C[i]; } delete[] C; //----------------------------------------------------------- return(0); } </code></pre>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USAjay Karthik
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COwhat kind of system are you running it on?
      singulars
      1. POMatrix multiplication of 10000 X 10000
      1. USDashControl
    2. CO@DashControl i have a remote connection to my university unix server using putty.
      singulars
      1. POMatrix multiplication of 10000 X 10000
      1. USAjay Karthik
 

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