openacc

问题 I'm trying to build the simplest OpenMP or OpenACC C++ program with GPU offload using gcc-10, CUDA 11 on Ubuntu 18.04 and this CMakeLists.txt file (or OpenMP version): cmake_minimum_required(VERSION 3.18) project(hello VERSION 0.1.0) find_package(OpenACC REQUIRED) add_executable(hello main.cpp) target_compile_options(hello PRIVATE -O3 -fopenacc -foffload=nvptx-none) target_link_libraries (hello OpenACC::OpenACC_CXX) The build fails with: [build] [100%] Linking CXX executable hello [build]

问题 I'm trying to build the simplest OpenMP or OpenACC C++ program with GPU offload using gcc-10, CUDA 11 on Ubuntu 18.04 and this CMakeLists.txt file (or OpenMP version): cmake_minimum_required(VERSION 3.18) project(hello VERSION 0.1.0) find_package(OpenACC REQUIRED) add_executable(hello main.cpp) target_compile_options(hello PRIVATE -O3 -fopenacc -foffload=nvptx-none) target_link_libraries (hello OpenACC::OpenACC_CXX) The build fails with: [build] [100%] Linking CXX executable hello [build]

问题 I am writing a simple test code to see how I could wrap a fortran code containing openacc regions and call from python. Here's the code. module test use iso_c_binding, only: sp => C_FLOAT, dp => C_DOUBLE, i8 => C_INT implicit none contains subroutine add (a, b, n, c) integer(kind=i8), intent(in) :: n real(kind=dp), intent(in) :: a(n) real(kind=dp), intent(in) :: b(n) real(kind=dp), intent(out) :: c(n) integer(kind=i8) :: i !$acc enter data create(a, b, c) do i = 1, n c(i) = a(i) + b(i) end do

问题 I am writing a simple test code to see how I could wrap a fortran code containing openacc regions and call from python. Here's the code. module test use iso_c_binding, only: sp => C_FLOAT, dp => C_DOUBLE, i8 => C_INT implicit none contains subroutine add (a, b, n, c) integer(kind=i8), intent(in) :: n real(kind=dp), intent(in) :: a(n) real(kind=dp), intent(in) :: b(n) real(kind=dp), intent(out) :: c(n) integer(kind=i8) :: i !$acc enter data create(a, b, c) do i = 1, n c(i) = a(i) + b(i) end do

问题 When trying to compile OpenACC code with GCC-9.3.0 (g++) configured with --enable-languages=c,c++,lto --disable-multilib the following code does not use multiple cores, whereas if the same code is compiled with the pgc++ compiler it does use multiple cores. g++ compilation: g++ -lgomp -Ofast -o jsolve -fopenacc jsolvec.cpp pgc++ compilation: pgc++ -o jsolvec.exe jsolvec.cpp -fast -Minfo=opt -ta=multicore Code from OpenACC Tutorial1/solver https://github.com/OpenACCuserGroup/openacc-users

问题 Please, help. 1) I need to use memcpy for moving the arrays allocated on the gpu. i can not use std::memcpy because it "has no acc routine" (compiler output). My code is const int GL=100000; Particle particles[GL]; int cp01[2][GL]; #pragma acc declare create(particles,cp01) ... i read that cudaMemcpy can be used with openacc. In function_device() (not able to fill the array allocated on the gpu) i call from the host #pragma acc data copy(cp) { cudaMemcpy(&particles[cp01[0][0]],&particles[cp01

问题 I have a C program to find whether 2 sets of polygons are overlapped. User input 2 sets of polygon (each set of data has several thousands polygons) and the program see which polygon in set1 overlap with which polygon in set2 I have 2 struct like these: struct gpc_vertex /* Polygon vertex */ { double x; double y; }; struct gpc_vertex_list /* Polygon contour */ { int pid; // polygon id int num_vertices; double *mbr; // minimum bounding rectangle of the polygon, so always 4 elements }; I have

问题 I would like to know how to link a pgc++ compiled code (blabla.a) with a main code compiled with c++ or g++ GNU compiler. For the moment linking with default gnu c++ linker gives errors like: undefined reference to `__pgio_initu' 回答1: As the previous person already pointed out, PGI supports G++ name mangling when using the pgc++ command. Judging from this output, I'm guessing that you're linking with g++ rather than pgc++. I've had the most success when using pgc++ as the linker so that it

问题 I study a lot of articles and the manual of OpenACC but still i don't understand the main difference of these two constructs. 回答1: kernels directive is the more general case and probably one that you might think of, if you've written GPU (e.g. CUDA) kernels before. kernels simply directs the compiler to work on a piece of code, and produce an arbitrary number of "kernels", of arbitrary "dimensions", to be executed in sequence, to parallelize/offload a particular section of code to the

问题 I study a lot of articles and the manual of OpenACC but still i don't understand the main difference of these two constructs. 回答1: kernels directive is the more general case and probably one that you might think of, if you've written GPU (e.g. CUDA) kernels before. kernels simply directs the compiler to work on a piece of code, and produce an arbitrary number of "kernels", of arbitrary "dimensions", to be executed in sequence, to parallelize/offload a particular section of code to the