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.

diff --git a/Lib/test/libregrtest/cmdline.py b/Lib/test/libregrtest/cmdline.py
index 9f1bf6800824a617e92dc2ad8d265f48705085b9..c8fedc7ad329bd5080857ab2764f3b1b5e6264ec 100644 (file)
--- a/Lib/test/libregrtest/cmdline.py
+++ b/Lib/test/libregrtest/cmdline.py
@@ -264,7 +264,9 @@ def _create_parser():
                        help='only write the name of test cases that will be run'
                             ' , don\'t execute them')
     group.add_argument('-P', '--pgo', dest='pgo', action='store_true',
-                       help='enable Profile Guided Optimization training')
+                       help='enable Profile Guided Optimization (PGO) training')
+    group.add_argument('--pgo-extended', action='store_true',
+                       help='enable extended PGO training (slower training)')
     group.add_argument('--fail-env-changed', action='store_true',
                        help='if a test file alters the environment, mark '
                             'the test as failed')
@@ -344,6 +346,8 @@ def _parse_args(args, **kwargs):
         parser.error("-G/--failfast needs either -v or -W")
     if ns.pgo and (ns.verbose or ns.verbose2 or ns.verbose3):
         parser.error("--pgo/-v don't go together!")
+    if ns.pgo_extended:
+        ns.pgo = True  # pgo_extended implies pgo
 
     if ns.nowindows:
         print("Warning: the --nowindows (-n) option is deprecated. "

diff --git a/Lib/test/libregrtest/main.py b/Lib/test/libregrtest/main.py
index e2274254fdb89cd9c37d8b09ac67845394e2cbc1..78b6790685c9df880c32f1a6f427c016eff755e7 100644 (file)
--- a/Lib/test/libregrtest/main.py
+++ b/Lib/test/libregrtest/main.py
@@ -17,6 +17,7 @@ from test.libregrtest.runtest import (
     INTERRUPTED, CHILD_ERROR, TEST_DID_NOT_RUN,
     PROGRESS_MIN_TIME, format_test_result, is_failed)
 from test.libregrtest.setup import setup_tests
+from test.libregrtest.pgo import setup_pgo_tests
 from test.libregrtest.utils import removepy, count, format_duration, printlist
 from test import support
 
@@ -214,6 +215,9 @@ class Regrtest:
 
         removepy(self.tests)
 
+        # add default PGO tests if no tests are specified
+        setup_pgo_tests(self.ns)
+
         stdtests = STDTESTS[:]
         nottests = NOTTESTS.copy()
         if self.ns.exclude:

diff --git a/Lib/test/libregrtest/pgo.py b/Lib/test/libregrtest/pgo.py
new file mode 100644 (file)
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[:]

diff --git a/Makefile.pre.in b/Makefile.pre.in
index 94a1208efa094cecb04865ea5149649201aa9c01..dd267b483a29b1d04fe7d7bc7e371893cda66715 100644 (file)
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -255,9 +255,10 @@ TCLTK_INCLUDES=    @TCLTK_INCLUDES@
 TCLTK_LIBS=    @TCLTK_LIBS@
 
 # The task to run while instrumented when building the profile-opt target.
-# We exclude unittests with -x that take a rediculious amount of time to
-# run in the instrumented training build or do not provide much value.
-PROFILE_TASK=-m test.regrtest --pgo
+# To speed up profile generation, we don't run the full unit test suite
+# by default. The default is "-m test --pgo". To run more tests, use
+# PROFILE_TASK="-m test --pgo-extended"
+PROFILE_TASK=  @PROFILE_TASK@
 
 # report files for gcov / lcov coverage report
 COVERAGE_INFO= $(abs_builddir)/coverage.info

diff --git a/Misc/NEWS.d/next/Build/2019-07-11-01-28-24.bpo-36044.gIgfiJ.rst b/Misc/NEWS.d/next/Build/2019-07-11-01-28-24.bpo-36044.gIgfiJ.rst
new file mode 100644 (file)
index 0000000..177c4cb
--- /dev/null
+++ b/Misc/NEWS.d/next/Build/2019-07-11-01-28-24.bpo-36044.gIgfiJ.rst
@@ -0,0 +1,9 @@
+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.

diff --git a/configure b/configure
index 2c49d853a384a0b86ec403be463637e4c311a996..4cea98e3652896dc0cc6dc56676ef8dc2578b689 100755 (executable)
--- a/configure
+++ b/configure
@@ -686,6 +686,7 @@ target_vendor
 target_cpu
 target
 LLVM_AR
+PROFILE_TASK
 DEF_MAKE_RULE
 DEF_MAKE_ALL_RULE
 ABIFLAGS
@@ -856,6 +857,7 @@ LDFLAGS
 LIBS
 CPPFLAGS
 CPP
+PROFILE_TASK
 PKG_CONFIG
 PKG_CONFIG_PATH
 PKG_CONFIG_LIBDIR'
@@ -1559,6 +1561,8 @@ Some influential environment variables:
   CPPFLAGS    (Objective) C/C++ preprocessor flags, e.g. -I<include dir> if
               you have headers in a nonstandard directory <include dir>
   CPP         C preprocessor
+  PROFILE_TASK
+              Python args for PGO generation task
   PKG_CONFIG  path to pkg-config utility
   PKG_CONFIG_PATH
               directories to add to pkg-config's search path
@@ -6426,6 +6430,16 @@ else
   DEF_MAKE_RULE="all"
 fi
 
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking PROFILE_TASK" >&5
+$as_echo_n "checking PROFILE_TASK... " >&6; }
+if test -z "$PROFILE_TASK"
+then
+       PROFILE_TASK='-m test --pgo'
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $PROFILE_TASK" >&5
+$as_echo "$PROFILE_TASK" >&6; }
+
 # Make llvm-relatec checks work on systems where llvm tools are not installed with their
 # normal names in the default $PATH (ie: Ubuntu).  They exist under the
 # non-suffixed name in their versioned llvm directory.

diff --git a/configure.ac b/configure.ac
index cc31df866d522f057ccac9756fb8fd6b98cc34ba..b9759e12f89f746105611e1b8fb7659812dd3a71 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -1293,6 +1293,14 @@ else
   DEF_MAKE_RULE="all"
 fi
 
+AC_ARG_VAR(PROFILE_TASK, Python args for PGO generation task)
+AC_MSG_CHECKING(PROFILE_TASK)
+if test -z "$PROFILE_TASK"
+then
+       PROFILE_TASK='-m test --pgo'
+fi
+AC_MSG_RESULT($PROFILE_TASK)
+
 # Make llvm-relatec checks work on systems where llvm tools are not installed with their
 # normal names in the default $PATH (ie: Ubuntu).  They exist under the
 # non-suffixed name in their versioned llvm directory.