code-insiders; rust notebook with the evcxr kernel, cpu 8%

[springyworks]

Type: Bug

1. opening a tiny rust notebook with only the Jupyter extension (Microsoft) enabled > one core of my cpu is at 100% for the code-insiders process /snap/code-insiders/1977.... (using htop)
2. closing notebook stops excessive cpu activity

Note: with code stable instead of code-insiders i do not see described problem
-/-

VS Code version: Code - Insiders 1.101.0-insider (747d0bd, 2025-05-23T06:35:04.132Z)
OS version: Linux x64 6.11.0-26-generic snap
Modes:

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-8700 CPU @ 3.20GHz (12 x 4299)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: enabled video_encode: disabled_software vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: disabled_off webnn: disabled_off
Load (avg)	3, 2, 2
Memory (System)	46.96GB (30.94GB free)
Process Argv	--no-sandbox --force-user-env --crash-reporter-id 47e286f1-0673-4ddf-bde6-4935a3f46ee8
Screen Reader	no
VM	0%
DESKTOP_SESSION	ubuntu
XDG_CURRENT_DESKTOP	Unity
XDG_SESSION_DESKTOP	ubuntu
XDG_SESSION_TYPE	x11

Extensions (82)

Extension	Author (truncated)	Version
terminal-commands	adr	1.0.5
vscode-sqlite	ale	0.14.1
tsl-problem-matcher	amo	0.6.2
preview-tiff	ana	1.0.1
markdown-mermaid	bie	1.28.0
file-properties-viewer	bru	1.2.0
crabviz	cha	0.4.0
vscode-opennewinstance	chr	0.0.15
npm-intellisense	chr	1.4.5
path-intellisense	chr	2.10.0
vscode-clock	Com	0.0.1
esbuild-problem-matchers	con	0.0.3
vscode-eslint	dba	3.0.13
tsuml2-vscode	dem	0.0.4
f5anything	dis	1.2.0
docker	doc	0.7.0
typescript-notebook	don	2.0.6
file-properties	dsy	2.0.0
gitlens	eam	2025.5.2405
prettier-vscode	esb	11.0.0
dependi	fil	0.7.15
codespaces	Git	1.17.3
copilot	Git	1.323.1582
copilot-chat	Git	0.28.2025052301
vscode-pull-request-github	Git	0.111.2025052204
debug-visualizer	hed	2.4.0
realtime-debugging	hed	0.1.0
vscode-drawio	hed	1.9.250226013
plantuml	jeb	2.18.1
svg	joc	1.5.4
google-search	kam	0.0.1
vscode-toggle-terminal	kri	0.0.8
vscode-clangd	llv	0.1.33
vscode-filesize	mkx	3.2.2
vscode-containers	ms-	2.0.1
debugpy	ms-	2025.9.2025052001
python	ms-	2025.7.2025052301
vscode-pylance	ms-	2025.5.100
datawrangler	ms-	1.22.0
jupyter	ms-	2025.5.2025052301
tensorboard	ms-	2023.10.1002992421
remote-containers	ms-	0.414.0
remote-ssh-edit	ms-	0.87.0
remote-wsl	ms-	0.99.0
cmake-tools	ms-	1.20.53
cpptools	ms-	1.26.1
extension-test-runner	ms-	0.0.12
hexeditor	ms-	1.11.1
live-server	ms-	0.5.2025051902
makefile-tools	ms-	0.12.17
powershell	ms-	2025.0.0
remote-explorer	ms-	0.6.2025051209
vscode-speech	ms-	0.14.0
vscode-typescript-next	ms-	5.9.20250524
vscode-websearchforcopilot	ms-	0.1.2025052201
vsliveshare	ms-	1.0.5948
file-and-folder-icons	nex	1.0.4
terminal-keeper	ngu	1.1.53
autodocstring	njp	0.6.1
nsight-vscode-edition	nvi	2024.1.34572442
indent-rainbow	ode	8.3.1
paste-as-file	oxy	0.0.2
vscode-xml	red	0.29.2025051008
bash-debug	rog	0.3.9
svg-preview	Sim	2.8.3
app-developer-copilot	sin	2.0.9
vscode-fileutils	sle	3.10.3
blockly-vscode	spi	0.0.1
vscode-taskexplorer	spm	2.13.2
unique-window-colors	stu	1.0.51
even-better-toml	tam	0.21.2
properties	Thi	12.0.2
graphviz-interactive-preview	tin	0.3.5
pdf	tom	1.2.2
vscode-lldb	vad	1.11.4
intellicode-api-usage-examples	Vis	0.2.9
vscodeintellicode	Vis	1.3.2
vscodeintellicode-completions	Vis	2.0.1
wokwi-vscode	Wok	2.6.5
html-to-markdown	Yan	1.1.0
open-in-external-app	YuT	0.10.0
markdown-all-in-one	yzh	3.6.3

A/B Experiments

vsliv368:30146709
vspor879:30202332
vspor708:30202333
vspor363:30204092
vswsl492:30256197
pythonvspyt551cf:31249598
vscod805:30301674
c4g48928:30535728
a9j8j154:30646983
962ge761:30841072
dsvsc014:30777825
dsvsc015:30821418
2e7ec940:31000449
pythontbext0:30879054
cppperfnew:30980852
dwnewjupyter:31046869
pythonrstrctxt:31093868
nativeloc1:31118317
e80f6927:31120813
dwcopilot:31158714
c3hdf307:31184662
6074i472:31201624
dwoutputs:31242946
customenabled:31248079
hdaa2157:31222309
copilot_t_ci:31222730
g012b348:31231168
pythoneinst12:31251391
bgtreat:31252123
c7cif404:31309980
5b33h341:31304797
pythonpulldiag:31287486
6gi0g917:31259950
61ibe868:31282443
996jf627:31264550
pythonrdcb7:31268811
usemplatestapi:31297334
e6194696:31309975
jjjhb125:31275147
pythonfullctx:31296836
6518g693:31302842
pylancecolor:31288664
generatesymbolt:31280541
convertfstringf:31280702
gendocf:31280703
pylancequickfixt:31311477
923gi514:31310909
j97ad248:31306657
a2ijf515:31307742
convertlamdaf:31311570
hcc0i926:31313559

[amunger]

I wasn't able to repro with a quick check - is this particular to a specific notebook, or does it also happen when just creating a new one?
There isn't really anything in vs code core that would take up more CPU based on kernel type except for rendering output. Can you try switching some relevant extensions between pre-release and release to see if any of those make a difference?

[springyworks]

somehow i can't reproduce the problem at this time, i suspect something with rendering and the :dep evcxr_image = "1.1" .

this is an analysis i made earlier;

1. workarounds;
   a. using code-insiders; I can continue more or less after stopping (not kill) the offending code-insiders linux process
   b. go back to 'code stable'

   With code-insiders, additional analysis of problem

2. running a small rust notebook (with evcxr kernel) gives no problems

3. running a big :dep in a rust notebook that lives in a big crate, laat he probleem opnieuw zien

4. running the same notebook with JupyterLab , no problem

5. vscode process explorer shows zygote (8 144 146938) is at 8% CPU, something hangs there.

6. Linux has a 'code-insiders' process at cpu 8%, one core (of 12) is 100% loaded.

7. Sometimes code-insiders pops up with 'no response, keep waiting, close, reopen' options.

8. Closing the offending rust notebook (with evcxr kernel) stops the problem, all cpu-cores are at ease.

9. Bisecting extensions did not reveal a problem.

10. I uninstalled my rust-analyzer extension, no effect.

11. I switched back to the release for the Jupyter (Microsoft) vscode extension, no effect

12. process details with ps -p -o pid,ppid,%cpu,%mem,cmd ; reveals
    PID PPID %CPU %MEM CMD
    12611 5352 14.5 0.4 /snap/code-insiders/1979/usr/share/code-insiders/code-insiders --type=zygote --no-sandbox
    PID PPID %CPU %MEM CMD
    5352 5349 0.0 0.1 /snap/code-insiders/1979/usr/share/code-insiders/code-insiders --type=zygote --no-sandbox
    PID PPID %CPU %MEM CMD
    5349 3003 1.3 0.4 /snap/code-insiders/1979/usr/share/code-insiders/code-insiders --no-sandbox --force-user-env /home/rustuser/Desktop/report vscode performance.txt
    PID PPID %CPU %MEM CMD
    3003 1 0.0 0.0 /usr/lib/systemd/systemd --user
    -/-