Re: [PATCH v2 0/8] Run tests in parallel showing number of tests running

[Ian Rogers]

On Wed, Oct 16, 2024 at 4:49 PM Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
>
> On Fri, Oct 11, 2024 at 03:03:46PM -0700, Ian Rogers wrote:
> > Avoid waitpid so that stdout/stderr aren't destroyed prior to wanting
> > to read them for display. When running on a color terminal, display
> > the number of running tests (1 if sequential). To avoid previous
> > flicker, only delete and refresh the display line when it changes. An
> > earlier version of this code is here:
> > https://lore.kernel.org/lkml/20240701044236.475098-1-irogers@xxxxxxxxxx/
> >
> > Add a signal handler for perf tests so that unexpected signals are
> > displayed and test clean up is possible.
> >
> > In perf test add an "exclusive" flag that causes a test to be run with
> > no other test. Set this flag manually for C tests and via a
> > "(exclusive)" in the test description for shell tests. Add the flag to
> > shell tests that may fail when run with other tests.
> >
> > Change the perf test loop to run in two passes. For parallel
> > execution, the first pass runs all tests that can be run in parallel
> > then the 2nd runs remaining tests sequentially. This causes the
> > "exclusive" tests to be run last and with test numbers moderately out
> > of alignment.
> >
> > Change the default to be to run tests in parallel. Running tests in
> > parallel brings the execution time down to less than half.
> >
> > v2: Fix inaccurate remaining counts when running specific
> >     tests. Rename "remaining" to "active" to better reflect the
> >     testing behavior. Move the exclusive flag to test cases and not
> >     entire suites. Add more "(exclusive)" flags to test as
> >     suggested-by James Clark. Remove "(exclusive)" flag from test
> >     descriptions to keep the command line output more concise. Add
> >     James Clark's tested-by.
> >
> > Ian Rogers (8):
> >   tools subcmd: Add non-waitpid check_if_command_finished()
> >   perf test: Display number of active running tests
> >   perf test: Reduce scope of parallel variable
> >   perf test: Avoid list test blocking on writing to stdout
> >   perf test: Tag parallel failing shell tests with "(exclusive)"
> >   perf test: Add a signal handler around running a test
> >   perf test: Run parallel tests in two passes
> >   perf test: Make parallel testing the default
>
> Nice work!  It looks much better now.
>
> But I'm seeing more failures in parallel mode.  Maybe we want to
> keep the default serial mode for a little more.

As you say, I think we should be conservative and mark all tests that
need to serial/sequential/exclusive with the exclusive tag. If you
tell me the failing tests I can add them to 'perf test: Tag parallel
failing shell tests with "(exclusive)"' as I did for James Clark with
the ARM tests. I'd prefer we did the tagging rather than not enabling
parallel testing as otherwise I may never learn which tests fail for
people when run in parallel.

Thanks,
Ian

> >
> >  tools/lib/subcmd/run-command.c                |  33 +++
> >  tools/perf/tests/builtin-test.c               | 274 ++++++++++++------
> >  .../tests/shell/coresight/asm_pure_loop.sh    |   2 +-
> >  .../shell/coresight/memcpy_thread_16k_10.sh   |   2 +-
> >  .../coresight/thread_loop_check_tid_10.sh     |   2 +-
> >  .../coresight/thread_loop_check_tid_2.sh      |   2 +-
> >  .../shell/coresight/unroll_loop_thread_10.sh  |   2 +-
> >  tools/perf/tests/shell/list.sh                |   5 +-
> >  .../tests/shell/perftool-testsuite_report.sh  |   2 +-
> >  tools/perf/tests/shell/record.sh              |   2 +-
> >  tools/perf/tests/shell/record_lbr.sh          |   2 +-
> >  tools/perf/tests/shell/record_offcpu.sh       |   2 +-
> >  tools/perf/tests/shell/stat_all_pmu.sh        |   2 +-
> >  tools/perf/tests/shell/test_arm_coresight.sh  |   2 +-
> >  .../tests/shell/test_arm_coresight_disasm.sh  |   2 +-
> >  tools/perf/tests/shell/test_arm_spe.sh        |   2 +-
> >  tools/perf/tests/shell/test_intel_pt.sh       |   2 +-
> >  .../perf/tests/shell/test_stat_intel_tpebs.sh |   2 +-
> >  tools/perf/tests/task-exit.c                  |   9 +-
> >  tools/perf/tests/tests-scripts.c              |   7 +-
> >  tools/perf/tests/tests.h                      |   9 +
> >  tools/perf/util/color.h                       |   1 +
> >  22 files changed, 258 insertions(+), 110 deletions(-)
> >
> > --
> > 2.47.0.rc1.288.g06298d1525-goog
> >