High CPU usage and Extension Host output flooded with messages

[Thalos12]

Hi, I am experiencing a strange issue, but unsure if this needs to be a new GitHub issue.

After some time that I am coding in Jupyter (I cannot say exactly how much, but seems like from 10 to 45 minutes) the CPU shows constant 100%+ usage, the Extension Host output gets flooded with messages (see the screencast below) and the only way to stop this is closing or reloading VSCode.

Screencast of Extension Host output flooding on Drive

Another symptom I noticed is the suggestions and hover panel appearing much much slower than usual.

The high CPU usage drains my laptop's battery quickly, any idea what might be causing this? I can provide more info if needed.

[DonJayamanne]

I believe this should be fixed in the latest pre-release version of the Jupyter extension.
please can you try installing the latest pre-release version of the Jupyter extension.
(you'll need the latest VS Code Insiders for this).

Duplicate of #15194

[Thalos12]

I have been using it for a couple of hours without issues, so I am inclined to think that the main issue is resolved. Thank you!

However, the slowness of the hover and suggestion panels is still occurring, and I noticed that sometimes it is accompanied by freezing of the whole window. Is that another known issue?

[DonJayamanne]

ave been using it for a couple of hours without issues, so I am inclined to think that the main issue is resolved. Thank you!

Thats great news, and thanks for getting back with a confirmation of the fix

However, the slowness of the hover and suggestion panels is still occurring, and I noticed that sometimes it is accompanied by freezing of the whole window. Is that another known issue?

Please can you file a github issue for this and please share the logs from the Jupyter output panel when filing the issue.
Here are instructions for getting the logs (again, please file a new issue)

• Open settings & go into Jupyter->Logging
• Change the value to verbose
• Reload VS Code,
• Attempt to repro the issue & then copy the output from the Jupyter output panel.

[Thalos12]

Just a brief update before opening a new issue. Playing with the "output" tabs, I found out that when VSCode freezes the jupyter tab shows very little

17:52:58.076 [info] End cell 46 execution after 0.491s, completed @ 1708534378074, started @ 1708534377583
17:52:58.076 [debug] Cell 46 executed with an error
17:53:17.054 [info] Handle Execution of Cells 46 for ~/WORK/DUETS/jeppe_single_stars/sample4jeppe.ipynb
17:53:17.056 [debug] Cell Index:46 sent to kernel
17:53:17.060 [debug] Start cell 46 execution @ 1708534397060 (clear output)
17:53:17.060 [info] Kernel acknowledged execution of cell 46 @ 1708534397060
17:53:17.083 [info] End cell 46 execution after 0.023s, completed @ 1708534397083, started @ 1708534397060
17:53:17.083 [debug] Cell 46 executed successfully
17:53:25.109 [debug] Jupyter completion time: 26
17:53:34.451 [debug] Jupyter completion time: 23
17:53:34.940 [debug] Jupyter completion time: 11

However, the window tab shows

2024-02-21 17:53:34.248 [warning] [perf] Renderer reported VERY LONG TASK (5717ms), starting profiling session '564ba7aa-6c3b-42ac-9473-12c496463a7f'
2024-02-21 17:53:41.054 [error] PerfSampleError: by <<renderer>> in (anonymous)#workbench.desktop.main.js:3:230279: 
	 at (anonymous) (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:230279)
	 at (anonymous) (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:215008)
	 at rt (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:230252)
	 at ot (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:230318)
	 at Dn.e.sanitize (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:233406)
	 at $ (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:242:4974)
	 at d (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:242:1301)
	 at render (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:659:30156)
	 at t (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:729:23573)
	 at render (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:729:21965)
	 at (anonymous) (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:729:25643)
	 at y (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:87:1814)
	 at fire (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:87:2006)
	 at y (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:648:24223)
2024-02-21 17:53:41.055 [error] PerfSampleError: by <<renderer>> in (anonymous)#workbench.desktop.main.js:242:5737: 
	 at (anonymous) (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:242:5737)
	 at (anonymous) (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:215008)
	 at rt (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:230252)
	 at ot (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:230318)
	 at Dn.e.sanitize (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:233406)
	 at $ (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:242:4974)
	 at d (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:242:1301)
	 at render (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:659:30156)
	 at t (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:729:23573)
	 at render (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:729:21965)
	 at (anonymous) (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:729:25643)
	 at y (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:87:1814)
	 at fire (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:87:2006)
	 at y (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:648:24223)
2024-02-21 17:53:41.056 [error] PerfSampleError: by <<renderer>> in (anonymous)#workbench.desktop.main.js:3:215008: 
	 at (anonymous) (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:215008)
	 at rt (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:230252)
	 at ot (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:230318)
	 at Dn.e.sanitize (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:3:233406)
	 at $ (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:242:4974)
	 at d (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:242:1301)
	 at render (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:659:30156)
	 at t (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:729:23573)
	 at render (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:729:21965)
	 at (anonymous) (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:729:25643)
	 at y (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:87:1814)
	 at fire (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:87:2006)
	 at y (vscode-file://vscode-app/usr/share/code-insiders/resources/app/out/vs/workbench/workbench.desktop.main.js:648:24223)
2024-02-21 17:53:41.161 [info] [perf] stored profile to DISK 'file:///tmp/renderer-05b2ed.cpuprofile.json' 564ba7aa-6c3b-42ac-9473-12c496463a7f

I have the profile saved to disk, should I include it in the issue?

Thank you again.

[Thalos12]

I don't want to bother too much, but I realized the slowness in the hover and suggestion panels happens also in .py files.
Should I still open an issue here? I believe I should open an issue in the vscode-python repo instead, but asking to be sure.