pytest really slow with python3 on windows

[acerv]

Hello everyone,

my application has 320 tests, half created with unittest suite and half created with pytest.
Now I'm currently porting everything to python 3.7.5, so I started to test the application on python3.

The current setup is the following:
python 2.7: pytest 4.6.6
python 3.7: pytest 5.2.1

When it comes to linux, there's no substantial difference between python2.7 and python3.7: unittests complete in 8 minutes.

But when it comes to Windows, I'm having a HUGE difference between the two versions: python2.7 takes 8 minutes to complete unittests, but python3.7 takes exactly 30 minutes.

The point is that, on Windows with python3.7, the first 40% of tests take a normal amount of time, but then it starts to slow down and even really fast tests take forever.

Do you know what it could be?

Thanks,
Andrea

[blueyed]

Hard to tell, you could try profiling it: https://docs.python.org/3/library/profile.html
Also just knowing if it is CPU or I/O bound would be useful to know already.
I guess that maybe some of your test monkey-patches something that then causes a slowdown.
For that you could bisect your tests, i.e. only run the 2nd half first and see if it still happens, then cut it in half from there.

[acerv]

I took a look the old unittests logs coming from Jenkins. It looks like there's the same issue in python27, but it's way more moderated. There it's really hard to see it.

So I was wrong: the problem comes out with both python27 and python37 and it probably started from a certain pytest version.

Here it is the cProfile output after running unittests on Windows with python3.7.5 and pytest 5.2.

report.txt% stats 40
Fri Nov  8 14:05:03 2019    report.txt

		 48886808 function calls (48568247 primitive calls) in 2731.712 seconds

   Ordered by: internal time
   List reduced from 5945 to 40 due to restriction <40>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	 4595  494.668    0.108  494.676    0.108 {built-in method nt.listdir}
  9839/13  388.714    0.040  781.056   60.081 c:\.venv37\lib\shutil.py:369(_rmtree_unsafe)
	 9986  253.994    0.025  254.114    0.025 {method 'read' of '_io.TextIOWrapper' objects}
	25221  248.898    0.010  248.915    0.010 {built-in method nt.open}
	29831  246.374    0.008  490.989    0.016 {built-in method io.open}
	20614  158.504    0.008  158.522    0.008 {built-in method nt.stat}
	12876  154.750    0.012  154.752    0.012 {built-in method nt.unlink}
	 9840  120.518    0.012  120.518    0.012 {built-in method nt.scandir}
	 9839  120.288    0.012  120.288    0.012 {built-in method nt.rmdir}
	   97   74.874    0.772   74.874    0.772 {built-in method time.sleep}
	41301   74.359    0.002   74.359    0.002 {method 'acquire' of '_thread.lock' objects}
	 3923   57.305    0.015   57.305    0.015 {method 'read' of '_io.FileIO' objects}
	23679   55.967    0.002  716.666    0.030 c:\python\win_64\3.7.2\Lib\pathlib.py:1185(read_text)
	 3536   32.661    0.009   32.661    0.009 {method 'truncate' of '_io.FileIO' objects}
	 2884   32.497    0.011   32.497    0.011 c:\.venv37\lib\site-packages\colorama\win32.py:109(SetConsoleTextAttribute)
	 2500   23.918    0.010   23.918    0.010 {built-in method nt._isdir}
	15989   21.193    0.001   21.193    0.001 {method 'flush' of '_io.TextIOWrapper' objects}
	14939   16.523    0.001   16.537    0.001 {method 'write' of '_io.TextIOWrapper' objects}
	 1253   12.117    0.010   12.121    0.010 {built-in method nt.mkdir}
	 8100   10.070    0.001   10.070    0.001 {built-in method nt.dup2}
	  416    8.669    0.021    8.669    0.021 {built-in method nt._getfinalpathname}
	   55    8.628    0.157    8.628    0.157 {method 'connect' of '_socket.socket' objects}
	 7072    8.550    0.001    8.550    0.001 {method 'seek' of '_io.FileIO' objects}
	  512    8.139    0.016    8.139    0.016 {method 'read' of '_io.BufferedReader' objects}
   324986    8.135    0.000    8.135    0.000 {built-in method _winapi.WaitForSingleObject}
	  282    7.184    0.025   48.511    0.172 c:\.venv37\lib\site-packages\_pytest\cacheprovider.py:103(set)

[blueyed]

_rmtree_unsafe

Looks suspicious, since there have been changes in that area.
Would be good if you could git-bisect it to find what's causing it. You might explicitly want to skip commits not changing code (changelog etc) if you have to do this on CI / need a full test run to trigger it.

[acerv]

I'm not sure about that call. I just run pytest disabling cacheprovider plugin with the command:

python -m cProfile -o report.txt -m pytest -o log_cli=false -p no:cacheprovider

and this is what I got back from the report (700 seconds less):

Welcome to the profile statistics browser.
report.txt% help

Documented commands (type help <topic>):
========================================
EOF  add  callees  callers  help  quit  read  reverse  sort  stats  strip

report.txt% sort time
report.txt% stats 40
Fri Nov  8 16:28:03 2019    report.txt

		 48283218 function calls (47971800 primitive calls) in 2074.651 seconds

   Ordered by: internal time
   List reduced from 6324 to 40 due to restriction <40>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	 4719  533.415    0.113  533.424    0.113 {built-in method nt.listdir}
	25286  269.811    0.011  269.828    0.011 {built-in method nt.open}
	10007  259.078    0.026  259.203    0.026 {method 'read' of '_io.TextIOWrapper' objects}
	29894  252.105    0.008  517.338    0.017 {built-in method io.open}
	21369  174.214    0.008  174.233    0.008 {built-in method nt.stat}
	   97   74.892    0.772   74.892    0.772 {built-in method time.sleep}
	23748   67.182    0.003  754.675    0.032 c:\python\win_64\3.7.2\Lib\pathlib.py:1185(read_text)
	 4177   66.078    0.016   66.078    0.016 {method 'read' of '_io.FileIO' objects}
   851/15   34.247    0.040   68.953    4.597 c:\.venv37\lib\shutil.py:369(_rmtree_unsafe)
	 3536   32.536    0.009   32.536    0.009 {method 'truncate' of '_io.FileIO' objects}
	 2851   31.215    0.011   31.215    0.011 c:\.venv37\lib\site-packages\colorama\win32.py:109(SetConsoleTextAttribute)
	 2500   24.553    0.010   24.553    0.010 {built-in method nt._isdir}
	15908   21.034    0.001   21.034    0.001 {method 'flush' of '_io.TextIOWrapper' objects}
	 1518   17.593    0.012   17.595    0.012 {built-in method nt.unlink}
	42553   17.445    0.000   17.445    0.000 {method 'acquire' of '_thread.lock' objects}
	14244   15.453    0.001   15.481    0.001 {method 'write' of '_io.TextIOWrapper' objects}
	 1253   13.161    0.011   13.166    0.011 {built-in method nt.mkdir}
	 8100   11.673    0.001   11.673    0.001 {built-in method nt.dup2}
	  852   10.297    0.012   10.297    0.012 {built-in method nt.scandir}
	  851   10.060    0.012   10.060    0.012 {built-in method nt.rmdir}

[acerv]

I also traced the same execution in linux to check if I'm having so many access to the storage memory, but it looks ok:

report_linux.bin% stats 30
Fri Nov  8 15:41:05 2019    report_linux.bin

		 50119799 function calls (50069719 primitive calls) in 437.503 seconds

   Ordered by: internal time
   List reduced from 4096 to 30 due to restriction <30>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	   93   93.439    1.005   93.439    1.005 {built-in method time.sleep}
  4071455   52.131    0.000   52.131    0.000 {built-in method posix.waitpid}
	 8085   41.102    0.005   41.102    0.005 {method 'write' of '_io.TextIOWrapper' objects}
	 7158   39.026    0.005   39.026    0.005 {method 'flush' of '_io.TextIOWrapper' objects}
	 6229   21.208    0.003   21.208    0.003 {built-in method posix.lstat}
  4074254   20.485    0.000   42.235    0.000 /home/acer/.pyenv/versions/3.7.5/lib/python3.7/subprocess.py:1573(_internal_poll)
  4076820   17.143    0.000   17.143    0.000 {method 'acquire' of '_thread.lock' objects}
	 4984   13.313    0.003   13.314    0.003 {built-in method posix.stat}
  4073765   10.980    0.000   25.445    0.000 /home/acer/.pyenv/versions/3.7.5/lib/python3.7/queue.py:96(empty)

[blueyed]

Try with -s (to bypass capturing). It looks like it is due to creating many tempfiles (#6034 might help here).
How many tests are there in total?

[blueyed]

Since it only happens after a while it might be related to many entries in the directory, and/or disk filling up?
Try looking at the open file descriptors of the python process, and the location (directory) where the temporary files are created.
Also the "sleep" looks suspicious?

[acerv]

I'll give you the next results when I'm back to the workstation.

time.sleep is used inside unittests and it's ok

[acerv]

I explain better how tests are made: unittests are built in 2 different suites. There's one suite written in plain unittest (core library) and a second suite written in pytest, testing my own pytest plugins using pytester. Indeed, my application is a customization of pytest with 17 plugins.

The total amount of tests is the following:

• core: 224 tests
• plugins: 126 tests

I noticed that pytest starts to slow down when switching from plain core library unittests to the pytest plugins tests. So I run suites splitted in 2 different sessions and, in this way, pytest stops into a correct amount of time.

All suites run wiith -s option:

profile.bin% stats 30
Sat Nov  9 08:34:22 2019    profile.bin

		 34056808 function calls (33862579 primitive calls) in 1028.837 seconds

   Ordered by: internal time
   List reduced from 5030 to 30 due to restriction <30>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	 2005  321.221    0.160  321.226    0.160 {built-in method nt.listdir}
	11759  100.258    0.009  100.275    0.009 {built-in method nt.stat}
	 7199   99.003    0.014   99.014    0.014 {built-in method nt.open}
	 2632   92.115    0.035   92.152    0.035 {method 'read' of '_io.TextIOWrapper' objects}
	 9386   90.904    0.010  187.620    0.020 {built-in method io.open}
	   90   71.312    0.792   71.312    0.792 {built-in method time.sleep}

The unittest suite:

profile.bin% stats 30
Sat Nov  9 08:38:38 2019    profile.bin

		 26180401 function calls (26126751 primitive calls) in 185.315 seconds

   Ordered by: internal time
   List reduced from 4120 to 30 due to restriction <30>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	   88   65.318    0.742   65.318    0.742 {built-in method time.sleep}
  2169968   24.969    0.000   24.969    0.000 {built-in method _winapi.WaitForSingleObject}
	  842   24.704    0.029   24.704    0.029 {method 'flush' of '_io.TextIOWrapper' objects}
	34226   11.738    0.000   11.738    0.000 {method 'acquire' of '_thread.lock' objects}
	   49   11.519    0.235   11.786    0.241 C:\.venv37\lib\shutil.py:96(copyfile)
	 4212    5.715    0.001    5.716    0.001 {built-in method nt.stat}

The pytest plugins suite:

profile.bin% stats 30
Sat Nov  9 08:42:12 2019    profile.bin

		 26513300 function calls (26255528 primitive calls) in 108.805 seconds

   Ordered by: internal time
   List reduced from 4780 to 30 due to restriction <30>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	  235   18.536    0.079   18.536    0.079 {method 'read' of '_io.BufferedReader' objects}
   168291   12.855    0.000   12.855    0.000 {built-in method _winapi.WaitForSingleObject}
		9    9.501    1.056    9.501    1.056 {built-in method time.sleep}
	16585    8.147    0.000    8.168    0.000 {built-in method nt.open}
	17144    8.072    0.000    8.097    0.000 {built-in method nt.stat}
	 4230    6.215    0.001    6.222    0.001 {built-in method nt.listdir}
	11849    4.336    0.000    4.336    0.000 {method 'acquire' of '_thread.lock' objects}
	20689    2.536    0.000   10.545    0.001 {built-in method io.open}
  1483950    1.901    0.000    1.901    0.000 {method 'match' of 're.Pattern' objects}
	 6257    1.709    0.000    1.767    0.000 {method 'read' of '_io.TextIOWrapper' objects}
   135817    1.322    0.000    1.322    0.000 {method 'search' of 're.Pattern' objects}
	 2200    1.021    0.000    1.021    0.000 {built-in method nt._isdir}

[blueyed]

Please git-bisect it, which would really be useful to know.
So using -s makes it twice as fast.
Also check --durations=50 to see which tests are the slowest there maybe.

[acerv]

No, -s is taking the same amount of time as before. I'm running the tests on a laptop now, because my workstation is in another place.

When you speak about "git-bisect", you mean to try different pytest versions until I find the one causing the problem, right?

[acerv]

I downloaded the 5.2.2 source code and tried to run pytest on your unittests.

    (.venv37) C:\userdata\pytest-5.2.2>python -m cProfile -o profile.bin -m pytest

Well...this is the result:

profile.bin% stats 30
Sat Nov  9 11:17:15 2019    profile.bin

		 332214759 function calls (329005244 primitive calls) in 1502.017 seconds

   Ordered by: internal time
   List reduced from 14532 to 30 due to restriction <30>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	  221  383.738    1.736  383.738    1.736 {built-in method _winapi.WaitForSingleObject}
   377557  186.926    0.000  187.591    0.000 {built-in method nt.stat}
	81772  129.167    0.002  129.326    0.002 {built-in method nt.listdir}
	  562   70.238    0.125   70.238    0.125 {method 'acquire' of '_thread.lock' objects}
	86416   45.911    0.001   46.085    0.001 {built-in method nt.open}
  1771277   36.165    0.000   36.165    0.000 {method 'search' of 're.Pattern' objects}
   157591   33.430    0.000   76.750    0.000 {built-in method io.open}
  8971618   23.913    0.000   23.913    0.000 {method 'match' of 're.Pattern' objects}
	35550   17.761    0.000   17.761    0.000 {built-in method nt._isdir}
  9026161   15.640    0.000   29.288    0.000 c:\python\win_64\3.7.2\Lib\ast.py:184(iter_child_nodes)
  7490161   14.202    0.000   22.737    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:657(_from_parsed_parts)
  7390202   13.271    0.000   35.576    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:1011(_make_child_relpath)
	 6994   13.131    0.002  102.569    0.015 C:\userdata\pytest-5.2.2\.venv37\lib\site-packages\_pytest\pathlib.py:101(find_prefixed)
20201499/20175842   13.099    0.000   29.388    0.000 {built-in method builtins.getattr}
	 7341   11.454    0.002   11.454    0.002 {built-in method builtins.compile}
  7444176   10.333    0.000  147.245    0.000 c:\win_64\3.7.2\Lib\pathlib.py:1068(iterdir)
   201038    9.832    0.000    9.832    0.000 {built-in method builtins.dir}

It looks like it's generally a python problem on windows operating system.

Are you testing pytest on windows? Because it looks like the problem is affecting also your unittesting suite.

[blueyed]

When you speak about "git-bisect", you mean to try different pytest versions until I find the one causing the problem, right?

Yes, you can start with tags/releases, but in general you would install pytest editable, and then (after verifying that the current commit, e.g. the features branch, is bad), run git bisect bad - it will ask you to start git-bisecting, and then you select a good commit, do git bisect good there, and from there on it will bisect the commits (try the middle). This is a bit tedious here since we have many (IMHO) unnecessary commits, so when you land on a "add changelog" or "add author" commit you can do "git bisect --skip" (since it appears to take a while for you to verify it -- for this it might be helpful if you could isolate it, so that it is reproducable in minites at least ;))

[blueyed]

find_prefixed (from the last dump) was added long ago alreadyy, d053cdf - so it is likely related to the whole tmpdir refactoring. /cc @RonnyPfannschmidt

[acerv]

find_prefixed is something introduced in pytest 3.9.0.
Now I'm testing unittests with pytest 3.6.0 and it looks like the problem is still there.

Anyway, when pytest starts to slow down, logging messages coming from logging library, as well as the stacktrace at the end of pytest execution, start to slow down, like if there's something in the terminal plugin trying to access data or to write/read somewhere.

[acerv]

I tried to perform some tests in order to understand what is the problem related with pytest execution. The following list try to focus on potential problems:

1. my own plugin implementation: I never run pytest on my own testing suite, to be sure it's not related with external implementations
2. pytest: executing pytest with and without cacheprovider/stdout redirection on file doesn't change pytest behaviour
3. Windows operating system: disable antivirus for temporary paths and where pytest is executing as well as all programs that might slow down pytest execution
4. python implementation: it looks like there's no substantial difference between python2 and python3, but in python3 the pytest execution looks a bit slower after a shorter amount of time than in python2

So my setup is the following:

• Windows 10
• python 3.7.2

All pytest profiling sessions have been executed on pytest unittesting suite, but I didn't see any huge difference between versions in terms of profiling. In all profiling sessions, it looks like pytest is causing lots of calls inside the nt module:

pytest 3.2.0

profile3.2.0.bin% stats 30
Tue Nov 12 10:47:37 2019    profile3.2.0.bin

		 281638670 function calls (279465487 primitive calls) in 200.360 seconds

   Ordered by: internal time
   List reduced from 11117 to 30 due to restriction <30>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	  116   56.623    0.488   56.623    0.488 {built-in method _winapi.WaitForSingleObject}
  1561619   26.438    0.000   26.438    0.000 {built-in method nt.stat}
 23810617   11.187    0.000   21.541    0.000 c:\python\win_64\3.7.2\Lib\ast.py:184(iter_child_nodes)
 30477608    5.685    0.000    7.939    0.000 c:\python\win_64\3.7.2\Lib\ast.py:172(iter_fields)
	 3796    5.674    0.001   38.628    0.010 C:\userdata\pytest\_pytest\_code\source.py:318(get_statement_startend2)
	   20    5.162    0.258    5.162    0.258 {built-in method time.sleep}
 11833347    5.012    0.000   30.755    0.000 c:\python\win_64\3.7.2\Lib\ast.py:224(walk)
 63119564    5.006    0.000    5.015    0.000 {built-in method builtins.isinstance}
28034530/28012220    4.021    0.000    4.411    0.000 {built-in method builtins.getattr}
  3473065    3.725    0.000    5.059    0.000 C:\userdata\pytest\.venv3\lib\ntpath.py:122(splitdrive)
 11829560    3.601    0.000   24.996    0.000 {method 'extend' of 'collections.deque' objects}
	 4968    3.481    0.001    3.481    0.001 {built-in method builtins.compile}
  1529425    2.532    0.000    7.169    0.000 C:\userdata\pytest\.venv3\lib\ntpath.py:75(join)
	21370    2.355    0.000    2.386    0.000 {built-in method io.open}
	 9733    1.632    0.000   31.647    0.003 C:\userdata\pytest\.venv3\lib\imp.py:254(find_module)
403309/50    1.321    0.000  200.229    4.005 C:\userdata\pytest\_pytest\vendored_packages\pluggy.py:598(execute)
	 4935    1.184    0.000    1.184    0.000 {built-in method nt.mkdir}
   102403    1.081    0.000    1.123    0.000 C:\userdata\pytest\_pytest\assertion\rewrite.py:177(mark_rewrite)
   293822    0.967    0.000    1.548    0.000 C:\userdata\pytest\_pytest\config.py:689(attrs)
   214317    0.952    0.000    1.859    0.000 C:\userdata\pytest\.venv3\lib\ntpath.py:450(normpath)
	 2899    0.942    0.000    0.942    0.000 {method 'close' of '_io.BufferedWriter' objects}
   298917    0.941    0.000    3.903    0.000 c:\python\win_64\3.7.2\Lib\argparse.py:1322(add_argument)
41223/41219    0.872    0.000    7.715    0.000 C:\userdata\pytest\_pytest\fixtures.py:1059(parsefactories)
	 3090    0.847    0.000    0.847    0.000 {method 'read' of '_io.BufferedReader' objects}
	43420    0.843    0.000    9.379    0.000 C:\userdata\pytest\_pytest\vendored_packages\pluggy.py:341(register)
  1353014    0.830    0.000   22.238    0.000 C:\userdata\pytest\.venv3\lib\genericpath.py:27(isfile)
  6548359    0.792    0.000    0.872    0.000 {built-in method nt.fspath}
 11829931    0.740    0.000    0.740    0.000 {method 'popleft' of 'collections.deque' objects}
	27382    0.706    0.000    0.706    0.000 {built-in method nt._isdir}
  4267083    0.686    0.000    0.686    0.000 {method 'replace' of 'str' objects}

pytest 3.9.1

profile.bin% stats 30
Tue Nov 12 11:33:32 2019    profile.bin

		 301261050 function calls (298634060 primitive calls) in 342.485 seconds

   Ordered by: internal time
   List reduced from 13112 to 30 due to restriction <30>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	  150  103.542    0.690  103.542    0.690 {built-in method _winapi.WaitForSingleObject}
  1923084   31.386    0.000   31.386    0.000 {method 'search' of 're.Pattern' objects}
  1596049   30.010    0.000   30.117    0.000 {built-in method nt.stat}
	36779   16.773    0.000   16.800    0.000 {built-in method nt.listdir}
  6432132    4.514    0.000    4.514    0.000 {method 'match' of 're.Pattern' objects}
	 1536    4.450    0.003    4.450    0.003 {built-in method nt.fsync}
   110608    4.256    0.000    6.505    0.000 {built-in method io.open}
  8449822    3.971    0.000    7.527    0.000 c:\python\win_64\3.7.2\Lib\ast.py:184(iter_child_nodes)
  3427154    3.914    0.000    5.310    0.000 C:\userdata\pytest\.venv3\lib\ntpath.py:122(splitdrive)
  6481354    3.322    0.000    5.302    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:657(_from_parsed_parts)
16946255/16938954    3.148    0.000    5.351    0.000 {built-in method builtins.getattr}
	 5755    3.071    0.001    3.071    0.001 {built-in method builtins.compile}
	55007    2.869    0.000    2.899    0.000 {built-in method nt.open}
	 5745    2.839    0.000   22.126    0.004 C:\userdata\pytest\.venv3\lib\site-packages\_pytest\pathlib.py:59(find_prefixed)
  6419455    2.799    0.000    8.017    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:1011(_make_child_relpath)
  3816940    2.758    0.000    5.061    0.000 C:\userdata\pytest\.venv3\lib\re.py:271(_compile)
 29430131    2.713    0.000    2.763    0.000 {built-in method builtins.isinstance}
  6451954    2.368    0.000   24.467    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:1068(iterdir)
  1369682    2.280    0.000    6.506    0.000 C:\userdata\pytest\.venv3\lib\ntpath.py:75(join)
	12125    2.271    0.000    2.306    0.000 {built-in method nt.mkdir}
376373/51    2.115    0.000  342.081    6.707 C:\userdata\pytest\.venv3\lib\site-packages\pluggy\callers.py:157(_multicall)
  6442722    2.002    0.000    2.401    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:770(name)
 10789283    1.985    0.000    2.737    0.000 c:\python\win_64\3.7.2\Lib\ast.py:172(iter_fields)
3753368/3753356    1.862    0.000    3.588    0.000 {method 'format' of 'str' objects}
   147836    1.795    0.000    1.795    0.000 {built-in method builtins.dir}
 12441487    1.727    0.000    1.727    0.000 {method 'startswith' of 'str' objects}
  4122414    1.714    0.000   10.505    0.000 c:\python\win_64\3.7.2\Lib\ast.py:224(walk)
  1798284    1.655    0.000   39.471    0.000 C:\userdata\pytest\.venv3\lib\site-packages\importlib_metadata\__init__.py:441(_matches_legacy)
  1983526    1.642    0.000    3.135    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:684(__str__)
	13032    1.567    0.000   29.044    0.002 C:\userdata\pytest\.venv3\lib\imp.py:254(find_module)

pytest 5.2.2

profile5.2.2.bin% stats 30
Tue Nov 12 10:58:24 2019    profile5.2.2.bin

		 340817062 function calls (337563837 primitive calls) in 351.518 seconds

   Ordered by: internal time
   List reduced from 14663 to 30 due to restriction <30>

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
	  221  104.700    0.474  104.700    0.474 {built-in method _winapi.WaitForSingleObject}
	  562   19.102    0.034   19.102    0.034 {method 'acquire' of '_thread.lock' objects}
	82033   18.169    0.000   18.214    0.000 {built-in method nt.listdir}
   379118    9.536    0.000    9.718    0.000 {built-in method nt.stat}
  1884134    7.073    0.000    7.073    0.000 {method 'search' of 're.Pattern' objects}
   181655    5.426    0.000    9.825    0.000 {built-in method io.open}
	 7365    5.183    0.001    5.184    0.001 {built-in method builtins.compile}
	 1717    5.130    0.003    5.130    0.003 {built-in method nt.fsync}
   110287    4.872    0.000    4.935    0.000 {built-in method nt.open}
 11229153    4.458    0.000    4.458    0.000 {method 'match' of 're.Pattern' objects}
  9029611    4.359    0.000    8.175    0.000 c:\python\win_64\3.7.2\Lib\ast.py:184(iter_child_nodes)
20430263/20404539    3.958    0.000    6.626    0.000 {built-in method builtins.getattr}
  7612892    3.916    0.000    6.289    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:657(_from_parsed_parts)
	 7030    3.587    0.001   28.639    0.004 C:\userdata\pytest\.venv3\lib\site-packages\_pytest\pathlib.py:101(find_prefixed)
   225256    3.285    0.000    3.285    0.000 {built-in method builtins.dir}
  7488996    3.284    0.000    9.399    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:1011(_make_child_relpath)
  7543118    2.807    0.000   28.648    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:1068(iterdir)
30453074/30453072    2.769    0.000    2.871    0.000 {built-in method builtins.isinstance}
  3560391    2.640    0.000    5.159    0.000 C:\userdata\pytest\.venv3\lib\re.py:271(_compile)
	12937    2.635    0.000    2.672    0.000 {built-in method nt.mkdir}
   670743    2.595    0.000    3.923    0.000 C:\userdata\pytest\.venv3\lib\site-packages\_pytest\config\argparsing.py:236(attrs)
  7505670    2.404    0.000    2.888    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:770(name)
 11550377    2.137    0.000    2.948    0.000 c:\python\win_64\3.7.2\Lib\ast.py:172(iter_fields)
4080082/4074956    2.095    0.000    4.072    0.000 {method 'format' of 'str' objects}
444844/56    2.082    0.000  351.137    6.270 C:\userdata\pytest\.venv3\lib\site-packages\pluggy\callers.py:157(_multicall)
   679209    2.059    0.000    8.818    0.000 c:\python\win_64\3.7.2\Lib\argparse.py:1322(add_argument)
  4409853    1.927    0.000   11.516    0.000 c:\python\win_64\3.7.2\Lib\ast.py:224(walk)
  2253560    1.894    0.000    3.486    0.000 c:\python\win_64\3.7.2\Lib\pathlib.py:684(__str__)
   398192    1.769    0.000    3.396    0.000 C:\userdata\pytest\.venv3\lib\ntpath.py:450(normpath)
 12516951    1.767    0.000    1.767    0.000 {method 'startswith' of 'str' objects}

[acerv]

Sorry If I complain about this close, but the bug is not fixed and I still have a difference of 30 minutes (!) between linux pytest executions and windows pytest execution when using python3.

[RonnyPfannschmidt]

@acerv it seems that tonight there has been a mishap and way more issues than intended where closed, we are currently looking trough them and reopen them as necessary

[acerv]

@RonnyPfannschmidt Thanks for your help.

I actually found what was the problem related with the tests. Moving from python2 to python3, there is a substantial difference on how multi threading has to be used, in order to avoid issues. According with my implementation, a particular thread was reading from a process stdout without exit, even if I called "join" and also killed the process manually.

This was causing some sort of a "slowliness" in all pytest tests, which were printing messages coming from logging module really really slow.

I'm not able to reproduce this bug at the moment, because I'm not at work, but I guess it's, first of all, my fault.

Thanks for your support anyway and for your great job with pytest.

[RonnyPfannschmidt]

@acerv thanks for the follow-up, please post a note when you took a look at the exact issue so we can have this as documentation for others that may face comparable issues

[Zac-HD]

Thanks @acerv - it sounds like this has been fixed or at least tracked down, so I'm closing the issue.