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Modify stencil example to do separate runs with and without task parallelism.

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This commit is contained in:
Matt Pharr
2011-08-30 05:08:21 -07:00
parent ad9e66650d
commit a94cabc692
2 changed files with 74 additions and 22 deletions
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37
examples/stencil/stencil.cpp
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@@ -116,20 +116,38 @@ int main() {
InitData(Nx, Ny, Nz, Aispc, vsq);
//
// Compute the image using the ispc implementation; report the minimum
// time of three runs.
// Compute the image using the ispc implementation on one core; report
// the minimum time of three runs.
//
double minISPC = 1e30;
double minTimeISPC = 1e30;
for (int i = 0; i < 3; ++i) {
reset_and_start_timer();
loop_stencil_ispc(0, 6, width, Nx - width, width, Ny - width,
width, Nz - width, Nx, Ny, Nz, coeff, vsq,
Aispc[0], Aispc[1]);
double dt = get_elapsed_mcycles();
minISPC = std::min(minISPC, dt);
minTimeISPC = std::min(minTimeISPC, dt);
}
printf("[stencil ispc]:\t\t\t[%.3f] million cycles\n", minISPC);
printf("[stencil ispc 1 core]:\t\t[%.3f] million cycles\n", minTimeISPC);
InitData(Nx, Ny, Nz, Aispc, vsq);
//
// Compute the image using the ispc implementation with tasks; report
// the minimum time of three runs.
//
double minTimeISPCTasks = 1e30;
for (int i = 0; i < 3; ++i) {
reset_and_start_timer();
loop_stencil_ispc_tasks(0, 6, width, Nx - width, width, Ny - width,
width, Nz - width, Nx, Ny, Nz, coeff, vsq,
Aispc[0], Aispc[1]);
double dt = get_elapsed_mcycles();
minTimeISPCTasks = std::min(minTimeISPCTasks, dt);
}
printf("[stencil ispc + tasks]:\t\t[%.3f] million cycles\n", minTimeISPCTasks);
InitData(Nx, Ny, Nz, Aserial, vsq);
@@ -137,19 +155,20 @@ int main() {
// And run the serial implementation 3 times, again reporting the
// minimum time.
//
double minSerial = 1e30;
double minTimeSerial = 1e30;
for (int i = 0; i < 3; ++i) {
reset_and_start_timer();
loop_stencil_serial(0, 6, width, Nx-width, width, Ny - width,
width, Nz - width, Nx, Ny, Nz, coeff, vsq,
Aserial[0], Aserial[1]);
double dt = get_elapsed_mcycles();
minSerial = std::min(minSerial, dt);
minTimeSerial = std::min(minTimeSerial, dt);
}
printf("[stencil serial]:\t\t[%.3f] millon cycles\n", minSerial);
printf("[stencil serial]:\t\t[%.3f] millon cycles\n", minTimeSerial);
printf("\t\t\t\t(%.2fx speedup from ISPC)\n", minSerial/minISPC);
printf("\t\t\t\t(%.2fx speedup from ISPC, %.2f from ISPC + tasks)\n",
minTimeSerial / minTimeISPC, minTimeSerial / minTimeISPCTasks);
// Check for agreement
int offset = 0;