Introduce benchmark test for rotate_cpx_vector

This commit introduces google benchmark library and one benchmark for rotate_cpx_vector. Also extracted common tools used in testcases for generation and allocation of byte aligned vectors in phy_test_tools.hpp
2024-08-28 15:08:44 +02:00
parent 46a1d2a621
commit 0883904891
6 changed files with 242 additions and 69 deletions
@@ -107,3 +107,65 @@ that directory directly, which you might also use to compare to the
   slight complication is due to using shell scripts. An easier way is to
   directly declare the executable in `add_test()`, and `ctest` will locate and
   run the executable properly.
+
+# Benchmarking
+
+Google benchmark can be used to profile and benchmark small pieces of code. See
+`benchmark_rotate_vector` for reference implementation. To start benchmarking code,
+write a benchmark first and compare your implementation against baseline result.
+To ensure your results are reproducible see this [guide](https://github.com/google/benchmark/blob/main/docs/reducing_variance.md)
+
+Example output follows:
+
+```bash
+2024-08-26T11:55:49+02:00
+Running ./openair1/PHY/TOOLS/tests/benchmark_rotate_vector
+Run on (8 X 4700 MHz CPU s)
+CPU Caches:
+  L1 Data 48 KiB (x4)
+  L1 Instruction 32 KiB (x4)
+  L2 Unified 1280 KiB (x4)
+  L3 Unified 12288 KiB (x1)
+Load Average: 0.51, 0.31, 0.29
+***WARNING*** CPU scaling is enabled, the benchmark real time measurements may be noisy and will incur extra overhead.
+---------------------------------------------------------------------
+Benchmark                           Time             CPU   Iterations
+---------------------------------------------------------------------
+BM_rotate_cpx_vector/100         43.1 ns         43.1 ns     16683136
+BM_rotate_cpx_vector/256         70.1 ns         70.0 ns      9647446
+BM_rotate_cpx_vector/1024         277 ns          277 ns      2378273
+BM_rotate_cpx_vector/4096        1070 ns         1070 ns       654792
+BM_rotate_cpx_vector/16384       4220 ns         4220 ns       169070
+BM_rotate_cpx_vector/20000       5288 ns         5289 ns       136190
+```
+
+## Comparing results
+
+Benchmark results can be output to json by using command line arguments, example below
+
+```bash
+./benchmark_rotate_vector --benchmark_out=file.json --benchmark_repetitions=10
+```
+
+These results can be compared by a tool provided with google benchmark
+
+```bash
+./compare.py benchmarks ../../file.json ../../file1.json
+```
+
+Example output:
+```
+Comparing ../../file.json to ../../file1.json
+Benchmark                                           Time             CPU      Time Old      Time New       CPU Old       CPU New
+--------------------------------------------------------------------------------------------------------------------------------
+BM_rotate_cpx_vector/100                         +0.3383         +0.3384            43            58            43            58
+BM_rotate_cpx_vector/100                         +0.2334         +0.2335            42            52            42            52
+BM_rotate_cpx_vector/100                         +0.1685         +0.1683            42            49            42            49
+BM_rotate_cpx_vector/100                         +0.1890         +0.1889            42            50            42            50
+BM_rotate_cpx_vector/100                         +0.0456         +0.0457            42            44            42            44
+BM_rotate_cpx_vector/100                         +0.0163         +0.0162            42            42            42            42
+BM_rotate_cpx_vector/100                         +0.0005         +0.0004            43            43            43            43
+BM_rotate_cpx_vector/100                         +0.0134         +0.0129            43            43            43            43
+BM_rotate_cpx_vector/100                         +0.0162         +0.0162            42            42            42            42
+BM_rotate_cpx_vector/100                         +0.0003         +0.0003            42            42            42            42
+```