High CPU usage with Jedi and MPLS

I’m still experiencing this issue: https://github.com/microsoft/vscode-python/issues/10263

It’s making this plugin completely unusable.

Environment data

• VS Code version: 1.44.2
• Extension version (available under the Extensions sidebar): 2020.5.80290
• OS and version: Mac OSX 10.15.1
• Python version (& distribution if applicable, e.g. Anaconda): 3.6.3
• Type of virtual environment used (N/A | venv | virtualenv | conda | …): venv
• Jedi or Language Server? (i.e. what is "python.jediEnabled" set to; more info #3977): Jedi Enabled = True
• Value of the python.languageServer setting: Microsoft

Expected behaviour

The plugin takes an undetectable amount of CPU capacity. I can open many tabs of python code. Tests run in a minute or two and don’t make the fan run or slow down the laptop.

Actual behaviour

Enabling the plugin and running tests spawns many python threads that use 100% of CPU capacity. Tests take 10+ minutes. The fan runs. Everything on the laptop slows down.

CPU usage appears to possibly be correlated to the number of tabs open.

Steps to reproduce:

1. Enable the plugin.
2. Open several tabs of python code.
3. Run tests with the test explorer.
4. Observe CPU usage.

With VS Code open, plugin disabled, no tabs open:

After opening 10 tabs:

After enabling plugin and reloading (no tabs open):

After opening 10 tabs with plugin enabled:

After starting tests with the test explorer:

After completing tests:

CPU usage stays maxed out even after the tests are done.

Logs

Output for Python in the Output panel (View→Output, change the drop-down the upper-right of the Output panel to Python)

User belongs to experiment group 'ShowPlayIcon - start'
User belongs to experiment group 'DebugAdapterFactory - experiment'
User belongs to experiment group 'PtvsdWheels37 - experiment'
User belongs to experiment group 'LS - control'
User belongs to experiment group 'UseTerminalToGetActivatedEnvVars - control'
User belongs to experiment group 'WebHostNotebook - control'
User belongs to experiment group 'LocalZMQKernel - control'
User belongs to experiment group 'NativeNotebook - control'
User belongs to experiment group 'CollectLSRequestTiming - control'
User belongs to experiment group 'CollectNodeLSRequestTiming - experiment'
User belongs to experiment group 'EnableIPyWidgets - experiment'
User belongs to experiment group 'RunByLine - control'
> conda --version
> pyenv root
> python3.7 ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.executable)"
> python3.6 ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.executable)"
> python3 ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.executable)"
> python2 ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.executable)"
> python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.executable)"
> conda info --json
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.executable)"
Starting Jedi Python language engine.
Python interpreter path: ~/mypackage/venv/bin/python
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import notebook"
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import jupyter"
> conda --version
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/testing_tools/run_adapter.py discover pytest -- --rootdir ~/mypackage/venv/mypackage-data -s --cache-clear
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.prefix)"
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.prefix)"
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.executable)"
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "import sys;print(sys.executable)"
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())"
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())"
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py site --user-site
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py site --user-site
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py jupyter kernelspec --version
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/completion.py
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/completion.py
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py flake8 --format=%(row)d,%(col)d,%(code).1s,%(code)s:%(text)s ~/mypackage/venv/mypackage-data/mypackage_data/pipe/models.py
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py flake8 --format=%(row)d,%(col)d,%(code).1s,%(code)s:%(text)s ~/mypackage/venv/mypackage-data/mypackage_data/pipe/models.py
cwd: ~/mypackage/venv/mypackage-data
> ~/mypackage/venv/bin/python ~/.vscode/extensions/ms-python.python-2020.5.80290/pythonFiles/pyvsc-run-isolated.py pytest --rootdir ~/mypackage/venv/mypackage-data --junitxml=/var/folders/xp/3xpd2x4j4zsf7vvvzd328cmh0000gn/T/tmp-243b2FToho3FOPs.xml
cwd: ~/mypackage/venv/mypackage-data

Output from Console under the Developer Tools panel (toggle Developer Tools on under Help; turn on source maps to make any tracebacks be useful by running Enable source map support for extension debugging)

XXXX

[kimadeline]

Hi everyone,

Is this issue still happening with the latest version of the extension?

We have also released a more performant language server called Pylance. You can download it from the marketplace and install it alongside the core Python extension. Feel free to give it a try instead of Jedi or MPLS and see if it helps 🙂

Thank you!

[kimadeline]

Since this was reported we have replaced our own custom Jedi integration with jedi-language-server, and deprecated the Microsoft option. I will be closing this issue, if you still encounter this problem with this new Jedi or Pylance, please open a new issue, so we can triage it appropriately.

Thanks!