bpo-36044: Reduce number of unit tests run for PGO build (GH-14702)
Reduce the number of unit tests run for the PGO generation task. This
speeds up the task by a factor of about 15x. Running the full unit test
suite is slow. This change may result in a slightly less optimized build
since not as many code branches will be executed. If you are willing to
wait for the much slower build, the old behavior can be restored using
'./configure [..] PROFILE_TASK="-m test --pgo-extended"'. We make no
guarantees as to which PGO task set produces a faster build. Users who
care should run their own relevant benchmarks as results can depend on
the environment, workload, and compiler tool chain.
(cherry picked from commit 4e16a4a3112161a5c6981c0588142d4a4673a934)
Co-authored-by: Neil Schemenauer <nas-github@arctrix.com>
diff --git a/Lib/test/libregrtest/pgo.py b/Lib/test/libregrtest/pgo.py
new file mode 100644
index 0000000..327f193
--- /dev/null
+++ b/Lib/test/libregrtest/pgo.py
@@ -0,0 +1,52 @@
+# Set of tests run by default if --pgo is specified. The tests below were
+# chosen based on the following criteria: either they exercise a commonly used
+# C extension module or type, or they run some relatively typical Python code.
+# Long running tests should be avoided because the PGO instrumented executable
+# runs slowly.
+PGO_TESTS = [
+ 'test_array',
+ 'test_base64',
+ 'test_binascii',
+ 'test_binop',
+ 'test_bisect',
+ 'test_bytes',
+ 'test_cmath',
+ 'test_codecs',
+ 'test_collections',
+ 'test_complex',
+ 'test_dataclasses',
+ 'test_datetime',
+ 'test_decimal',
+ 'test_difflib',
+ 'test_embed',
+ 'test_float',
+ 'test_fstring',
+ 'test_functools',
+ 'test_generators',
+ 'test_hashlib',
+ 'test_heapq',
+ 'test_int',
+ 'test_itertools',
+ 'test_json',
+ 'test_long',
+ 'test_math',
+ 'test_memoryview',
+ 'test_operator',
+ 'test_ordered_dict',
+ 'test_pickle',
+ 'test_pprint',
+ 'test_re',
+ 'test_set',
+ 'test_statistics',
+ 'test_struct',
+ 'test_tabnanny',
+ 'test_time',
+ 'test_unicode',
+ 'test_xml_etree',
+ 'test_xml_etree_c',
+]
+
+def setup_pgo_tests(ns):
+ if not ns.args and not ns.pgo_extended:
+ # run default set of tests for PGO training
+ ns.args = PGO_TESTS[:]