On 06/21/2019 11:38 AM, Cleber Rosa wrote:
On Fri, Jun 21, 2019 at 09:03:33AM +0200, Philippe Mathieu-Daudé wrote:
On 6/21/19 8:09 AM, Cleber Rosa wrote:
It's a fact that some tests may not be 100% reliable in all
environments. While it's a tough call to remove a useful test that
from the tree because it may fail every 1/100th time (or so), having
human attention drawn to known issues is very bad for humans and for
the projects they manage.
As a compromise solution, this marks tests that are known to have
issues, or that exercises known issues in QEMU or other components,
and excludes them from the entry point. As a consequence, tests
marked as "flaky" will not be executed as part of "make
check-acceptance".
Because such tests should be forgiven but never be forgotten, it's
possible to list them with (assuming "make check-venv" or "make
check-acceptance" has already initiatilized the venv):
$ ./tests/venv/bin/avocado list -t flaky tests/acceptance
It needs a Make target to run those flaky tests (If we ever agree on
this idea of flaky tests). Other Avocado flags are passed (e.g. -t for
tags) that can happen to fail tests on their absent. One clear example
is the spice test on patch 02 of this series...
Side note: check-acceptance seems to get growing in complexity that I
worry will end up in pitfalls. is a Make target the proper way to
implement complex test runs (I don't think so). Perhaps Avocado runner
concept could help somehow?
The current list of tests marked as flaky are a result of running
the entire set of acceptance tests around 20 times. The results
were then processed with a helper script[1]. That either confirmed
known issues (in the case of aarch64 and arm)[2] or revealed new
ones (mips).
This also bumps the Avocado version to one that includes a fix to the
parsing of multiple and mix "key:val" and simple tag values.
[1]
https://raw.githubusercontent.com/avocado-framework/avocado/master/contrib/scripts/summarize-job-failures.py
[2] https://bugs.launchpad.net/qemu/+bug/1829779
Signed-off-by: Cleber Rosa <cr...@redhat.com>
---
docs/devel/testing.rst | 17 +++++++++++++++++
tests/Makefile.include | 6 +++++-
tests/acceptance/boot_linux_console.py | 2 ++
tests/acceptance/linux_ssh_mips_malta.py | 2 ++
tests/requirements.txt | 2 +-
5 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/docs/devel/testing.rst b/docs/devel/testing.rst
index da2d0fc964..ff4d8e2e1c 100644
--- a/docs/devel/testing.rst
+++ b/docs/devel/testing.rst
@@ -574,6 +574,23 @@ may be invoked by running:
tests/venv/bin/avocado run $OPTION1 $OPTION2 tests/acceptance/
+Tagging tests
+-------------
+
+flaky
+~~~~~
+
+If a test is known to fail intermittently, even if only every one
+hundredth time, it's highly advisable to mark it as a flaky test.
+This will prevent these individual tests from failing much larger
+jobs, will avoid human interaction and time wasted to verify a known
+issue, and worse of all, can lead to the discredit of automated
+testing.
+
+To mark a test as flaky, add to its docstring.::
+
+ :avocado: tags=flaky
I certainly disagree with this patch, failing tests have to be fixed.
Why not tag all the codebase flaky and sing "happy coding"?
That's a great idea! :)
Now, seriously, I also resisted this for quite a long time. The
reality, though, is that intermittent failures will continue to
appear, and letting tests (and jobs, and CI pipelines, and whatnot)
fail is a very bad idea. We all agree that real fixes are better than
this, but many times they don't come quickly.
It seems to me that flaky test is just a case in a broaden scenario: run
(or not) grouped tests. You may have tests indeed broken or that takes
considerable time (those tagged "slow") which one may fairly want to
exclude from `make check-acceptance` as well. Thus some way to group
tests plus define run inclusion/exclusion patterns seems the ultimate
goal here.
Anyway if this get accepted, 'flaky' tags must have the intermittent
failure well described, and a Launchpad/Bugzilla tracking ticket referenced.
And here you have a key point that I absolutely agree with. The
"flaky" approach can either poison a lot of tests, and be seen as
quick way out of a difficult issue revealed by a test. Or, it can
serve as an effective tool to keep track of these very important
issues.
If we add:
# https://bugs.launchpad.net/qemu/+bug/1829779
:avocado: flaky
Topped with some human, I believe this can be very effective. This goes
without saying, but comments here are very much welcome.
I agree that all flaky test should have a tracking bug. In the end it
represents a technical debit that we should address.
- Wainer
- Cleber.
+
Manual Installation
-------------------
diff --git a/tests/Makefile.include b/tests/Makefile.include
index db750dd6d0..4c97da2878 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -1125,7 +1125,11 @@ TESTS_RESULTS_DIR=$(BUILD_DIR)/tests/results
# Any number of command separated loggers are accepted. For more
# information please refer to "avocado --help".
AVOCADO_SHOW=app
-AVOCADO_TAGS=$(patsubst %-softmmu,-t arch:%, $(filter
%-softmmu,$(TARGET_DIRS)))
+
+# Additional tags that are added to each occurence of "--filter-by-tags"
+AVOCADO_EXTRA_TAGS := ,-flaky
+
+AVOCADO_TAGS=$(patsubst
%-softmmu,--filter-by-tags=arch:%$(AVOCADO_EXTRA_TAGS), $(filter
%-softmmu,$(TARGET_DIRS)))
ifneq ($(findstring v2,"v$(PYTHON_VERSION)"),v2)
$(TESTS_VENV_DIR): $(TESTS_VENV_REQ)
diff --git a/tests/acceptance/boot_linux_console.py
b/tests/acceptance/boot_linux_console.py
index 32159503e9..6bd5c1ab53 100644
--- a/tests/acceptance/boot_linux_console.py
+++ b/tests/acceptance/boot_linux_console.py
@@ -249,6 +249,7 @@ class BootLinuxConsole(Test):
"""
:avocado: tags=arch:aarch64
:avocado: tags=machine:virt
+ :avocado: tags=flaky
"""
kernel_url = ('https://download.fedoraproject.org/pub/fedora/linux/'
'releases/29/Everything/aarch64/os/images/pxeboot/vmlinuz')
@@ -270,6 +271,7 @@ class BootLinuxConsole(Test):
"""
:avocado: tags=arch:arm
:avocado: tags=machine:virt
+ :avocado: tags=flaky
"""
kernel_url = ('https://download.fedoraproject.org/pub/fedora/linux/'
'releases/29/Everything/armhfp/os/images/pxeboot/vmlinuz')
diff --git a/tests/acceptance/linux_ssh_mips_malta.py
b/tests/acceptance/linux_ssh_mips_malta.py
index aafb0c39f6..ae70b658e0 100644
--- a/tests/acceptance/linux_ssh_mips_malta.py
+++ b/tests/acceptance/linux_ssh_mips_malta.py
@@ -208,6 +208,7 @@ class LinuxSSH(Test):
:avocado: tags=machine:malta
:avocado: tags=endian:big
:avocado: tags=device:pcnet32
+ :avocado: tags=flaky
"""
kernel_url = ('https://people.debian.org/~aurel32/qemu/mips/'
'vmlinux-3.2.0-4-5kc-malta')
@@ -222,6 +223,7 @@ class LinuxSSH(Test):
:avocado: tags=machine:malta
:avocado: tags=endian:little
:avocado: tags=device:pcnet32
+ :avocado: tags=flaky
"""
kernel_url = ('https://people.debian.org/~aurel32/qemu/mipsel/'
'vmlinux-3.2.0-4-5kc-malta')
diff --git a/tests/requirements.txt b/tests/requirements.txt
index 3ae0e29ad7..58d63d171f 100644
--- a/tests/requirements.txt
+++ b/tests/requirements.txt
@@ -1,5 +1,5 @@
# Add Python module requirements, one per line, to be installed
# in the tests/venv Python virtual environment. For more info,
# refer to: https://pip.pypa.io/en/stable/user_guide/#id1
-avocado-framework==68.0
+avocado-framework==69.1
paramiko
