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author: Dr Franck P. Vidal institute: School of Computer Science and Electronic Engineering, Bangor University, UK title: ICE4131 -- High Performance Computing subtitle: A Simple ray tracer to parallelise using PThread, OpenMP, MPI and CUDA.
A simple ray-tracer used as an example of application for my HPC module. The code was executed on two of my desktop PCs, with two different CPUs, using GNU/Linux openSUSE Leap 15.2. The same code was also executed on Supercomputing Wales with two different compilers (g++ 4.8.5 released in 2015 and icc 19.1.2.254 released in 2020). The code produces an 2048x2048 image as follows:
| Model name: | AMD FX(tm)-8350 Eight-Core Processor | Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz |
|---|---|---|---|
| CPU MHz: | 4000.000 | 4900.956 | 2401.000 |
| CPU max MHz: | 4000.0000 | 5000.0000 | 2401.000 |
| CPU min MHz: | 1400.0000 | 800.0000 | 1000.0000 |
| L1d cache: | 16K | 32K | 32K |
| L1i cache: | 64K | 32K | 32K |
| L2 cache: | 2048K | 256K | 1024K |
| L3 cache: | 8192K | 16384K | 28160K |
| NUMA node0 CPU(s): | 0-7 | 0-15 | 0,2,4,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,36,38 |
| NUMA node1 CPU(s): | none | none | 1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39 |
| Processor | Release date | Parallelisation | Release | Debug | Compiler |
|---|---|---|---|---|---|
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 80 threads | 85 | 396 | g++ 4.8.5 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 40 threads | 85 | 406 | g++ 4.8.5 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 24 threads | 124 | 627 | g++ 4.8.5 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 16 threads | 179 | 918 | g++ 4.8.5 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 8 threads | 352 | 1819 | g++ 4.8.5 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 4 threads | 657 | 3479 | g++ 4.8.5 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 1 thread | 2518 | 12977 | g++ 4.8.5 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | none | 2692 | 13040 | g++ 4.8.5 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 80 threads | 86 | 441 | icc 19.1.2.254 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 40 threads | 87 | 452 | icc 19.1.2.254 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 24 threads | 143 | 680 | icc 19.1.2.254 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 16 threads | 185 | 995 | icc 19.1.2.254 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 8 threads | 365 | 1959 | icc 19.1.2.254 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 4 threads | 702 | 3659 | icc 19.1.2.254 |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | OpenMP with 1 thread | 2639 | icc 19.1.2.254 | |
| Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz | Q1 2018 | none | 2683 | 14129 | icc 19.1.2.254 |
| AMD FX(tm)-8350 Eight-Core Processor | Q1 2018 | OpenMP with 80 threads | 585 | gcc 7.5.0 | |
| AMD FX(tm)-8350 Eight-Core Processor | Q1 2018 | OpenMP with 40 threads | 586 | gcc 7.5.0 | |
| AMD FX(tm)-8350 Eight-Core Processor | Q1 2018 | OpenMP with 24 threads | 583 | gcc 7.5.0 | |
| AMD FX(tm)-8350 Eight-Core Processor | Q1 2018 | OpenMP with 16 threads | 587 | gcc 7.5.0 | |
| AMD FX(tm)-8350 Eight-Core Processor | Q1 2018 | OpenMP with 8 threads | 606 | gcc 7.5.0 | |
| AMD FX(tm)-8350 Eight-Core Processor | Q1 2018 | OpenMP with 4 threads | 1050 | gcc 7.5.0 | |
| AMD FX(tm)-8350 Eight-Core Processor | Q1 2018 | OpenMP with 1 thread | 3981 | gcc 7.5.0 | |
| Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | Q4 2018 | OpenMP with 80 threads | 199 | 1067 | gcc 7.5.0 |
| Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | Q4 2018 | OpenMP with 40 threads | 204 | 1070 | gcc 7.5.0 |
| Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | Q4 2018 | OpenMP with 24 threads | 208 | 1077 | gcc 7.5.0 |
| Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | Q4 2018 | OpenMP with 16 threads | 209 | gcc 7.5.0 | |
| Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | Q4 2018 | OpenMP with 8 threads | 287 | 1371 | gcc 7.5.0 |
| Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | Q4 2018 | OpenMP with 4 threads | 515 | 2554 | gcc 7.5.0 |
| Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | Q4 2018 | OpenMP with 1 thread | 1911 | 9454 | gcc 7.5.0 |
| Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | Q4 2018 | none | 1884 | 9322 | gcc 7.5.0 |
In the plot below, x depicts the runtime when the program is compiled in Release mode, and + in Debug mode.
