tests: add benchmarking code for crc32 code / libs

src/borg/testsuite/test_crc32_bench.py

@@ -0,0 +1,53 @@
+# benchmark deflate crc32 against zlib crc32
+# note: we have other tests for correctness of the result, so we do not check it here.
+
+try:
+    import deflate
+except ImportError:
+    deflate = None
+
+import pytest
+import zlib
+
+from borg.algorithms.checksums import crc32_slice_by_8 as borg_crc32_slice8
+from borg.algorithms.checksums import crc32_clmul as borg_crc32_clmul
+from borg.algorithms.checksums import have_clmul
+
+import os
+
+data = os.urandom(10 * 1000000)
+
+CORRECT = zlib.crc32(data)
+
+
+def test_zlib_crc32(benchmark):
+    @benchmark
+    def result():
+        return zlib.crc32(data)
+
+    assert result == CORRECT
+
+
+@pytest.mark.skipif(not hasattr(deflate, 'crc32'), reason="deflate.crc32 not available")
+def test_deflate_crc32(benchmark):
+    @benchmark
+    def result():
+        return deflate.crc32(data)
+
+    assert result == CORRECT
+
+
+def test_borg_crc32_slice8(benchmark):
+    @benchmark
+    def result():
+        return borg_crc32_slice8(data)
+
+    assert result == CORRECT
+
+@pytest.mark.skipif(not have_clmul, reason="clmul not detected")
+def test_borg_crc32_clmul(benchmark):
+    @benchmark
+    def result():
+        return borg_crc32_clmul(data)
+
+    assert result == CORRECT