The python debugger is extremely slow

[DonJayamanne]

From @mjbvz on April 19, 2017 21:0

From @FuZhiyu on April 19, 2017 7:37

• VSCode Version: Code 1.11.2 (6eaebe3b9c70406d67c97779468c324a7a95db0e, 2017-04-13T07:56:42.517Z)
• OS Version: Darwin x64 16.5.0
• Extensions:

Extension	Author	Version
project-manager	alefragnani	0.14.0
gitignore	codezombiech	0.5.0
git-extension-pack	donjayamanne	0.1.2
githistory	donjayamanne	0.2.0
python	donjayamanne	0.6.2
gitlens	eamodio	3.4.5
sublime-keybindings	ms-vscode	2.0.1
vscode-open-in-github	ziyasal	1.2.3

---

Steps to Reproduce:

1. run the VSC debugger;
2. run the file in the console;
3. compare the speed.

Running in the VSC debugger is much slower than running it outside.

Copied from original issue: microsoft/vscode#25001

Copied from original issue: DonJayamanne/pythonVSCode#897

[DonJayamanne]

Please Define extremely slow.
Debugging applications will always be slower than running without debugging, that's an obvious fact.

So please define extremely slow, is it unusable? Please provide the sample code.

[DonJayamanne]

@FuZhiyu fyi

[DonJayamanne]

From @xoviat on April 20, 2017 17:38

@mjbvz this is actually somewhat your problem because pythonvscode uses the visual studio python debugger. However, I'm working to move to the pydev debugger, which is significantly faster.

[DonJayamanne]

Still haven't answered the questions.

[DonJayamanne]

@xoviat
How is this @mjbvz 's problem?

@mjbvz this is actually somewhat your problem because pythonvscode

[DonJayamanne]

From @xoviat on April 21, 2017 14:37

He works for Microsoft and the debugger is written by Microsoft. Now, I'm not asking him to fix this project's problems and I have no ill will towards Microsoft, but I am pointing out that the visual studio debugger probably has the same problems.

[DonJayamanne]

Lol. We can't start pointing fingers at anyone who works at Msft, just because you have a bunch that there is a problem with a piece of code written by sometime is some other totally different department.
Besides the problem could be with my implementation of the code, I don't think you have ruled that out.

I don't think it's a good idea to start pointing fingers on this manner. If you stay doing this, you only alienate people in the opens source community.

[DonJayamanne]

From @xoviat on April 21, 2017 23:3

I'm not blaming microsoft. I'm saying that they might need to fix their debugger for visual studio. I'm not complaining. I thought I made it clear that I had no problems with microsoft.

[DonJayamanne]

From @GiuseppeLaurenza on May 12, 2017 15:26

@xoviat There are any news about the inclusion of pydev debugger?

@DonJayamanne Some times with multithreading programming i see strange crash that i do not see with Pycharm (that use pydev) so i think that the problem is VS debugger. Also the performance of VS code in debug mode are poor with respect to the performance of Pycharm

[DonJayamanne]

From @xoviat on May 12, 2017 15:30

@GiuseppeLaurenza

I have an open pull request here: DonJayamanne#942

If you want to help, fork that and then fix the travis-ci tests.

[DonJayamanne]

From @GiuseppeLaurenza on May 12, 2017 15:33

@xoviat
Thanks for the fast reply. I hope that I can help. At the end of the next job deadline I try to help

[DonJayamanne]

From @lsternlicht on June 12, 2017 17:34

any idea of what changed here? I am also experiencing extremely slow debug

[DonJayamanne]

Nothing has changed in the extension to slow down the debugging experience. I'll check vscode.

[DonJayamanne]

From @imaia on July 17, 2017 18:24

Python debugging is quite slow here too. While pdb takes about 1s, in vs code, it takes up to two minutes.

[DonJayamanne]

From @rokkerruslan on July 30, 2017 7:23

Python 3.6.2 (default, Jul 20 2017, 08:43:29)
[GCC 5.4.1 20170519] on linux
Python debugging is very slow
PyCharm 3-6 seconds. VsCode 3-4 minutes (plus - no any output at console).

[DonJayamanne]

From @cefn on August 1, 2017 18:17

Confirm I am experiencing a slow debugger in Ubuntu Xenial 16:04. In the tests I was performing, PyCharm can debug from one point to another in the same codebase around 4 times faster than VSCode.

[DonJayamanne]

From @JulioV on August 3, 2017 8:48

Also in windows 10

[DonJayamanne]

From @GiuseppeLaurenza on August 3, 2017 8:55

i had the same problem on macOS Sierra

[DonJayamanne]

From @doomleika on August 10, 2017 4:10

Can confirm, it's so slow that I have to break out PyCharm for moderately computation expensive code

[DonJayamanne]

From @hatarist on August 10, 2017 4:14

Same here, it's insane (Sierra 10.12.6, VS Code 1.14.2), went back to pudb :o

[DonJayamanne]

From @sametmax on August 25, 2017 8:57

If I try to debug a flask process, I run the dev server. I measured that starting the server with the VSCode debugger is 22 times slower than starting it manually, which makes it unappealing compared to pdb.

[DonJayamanne]

From @Madder on September 6, 2017 10:58

The debugger is really unusable as it stands.
It's much slower compared to something like Spyder.

[DonJayamanne]

From @ghost on September 14, 2017 6:37

Encountered the same problem.

In debug mode,
"import tensorflow" cost more than 20 seconds;
"from tensorflow.examples.tutorials.mnist import input_data" cost more than 1 minute.

OS: macOS 10.12.6
VSCode: 1.16.0
Python: 0.7.0

[DonJayamanne]

From @EECSGEEK on September 26, 2017 7:24

TO DonJayamann

Please Define extremely slow.
Debugging applications will always be slower than running without debugging, that's an obvious fact.

Run a test.py
type "python test.py" in Terminal window, is much faster
than press double F5 to run it.

Is there any shortcut to switch cursor to Terminal window or Text edit windows?

Whats more, when mouse cursor in Terminal windows,
I press F5, the cursor doesn't switch to Debug Console Window.
So I must click to Debug Console Window to see the output,.

OS: win10 1703
VScode: 1.6.1

[DonJayamanne]

From @brettcannon on September 26, 2017 17:56

I believe the debugger situation is being evaluated at the moment in regards to pydevd, etc. so this may be changing in the future. Unfortunately there's no timeline, but people are aware of the desire for a different debugger option other than ptvsd.

[brettcannon]

Closing as a duplicate of #97

[ksknysn]

hi,
i read data from my disk. i read 3 mins with anaconda and mozilla. but i wait so long in vs. i can't understand problem.

[activaigor]

@DonJayamanne so we really don't know anything about how fast problem may be solved? seems like it is the last feature before people start moving from PyCharm to vscode

[smortaz]

As mentioned earlier, we are looking at major improvements in the debugger. You should see some announcements in the next few months! thanks for being patient.

…

On Thu, Feb 8, 2018 at 3:08 PM, Igor ***@***.***> wrote: @DonJayamanne <https://github.com/donjayamanne> so we really don't know anything about how fast problem may be solved? seems like it is the last feature before people start moving from PyCharm to vscode — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#106 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAtUVCjh4tHl0UowuaT8d9PkV_AcZOXAks5tS35QgaJpZM4Qciuv> .

[PhungXuanAnh]

Is there any improvement in the debugger, I am looking for it to switch to vscode

[DonJayamanne]

Please check the following issue for more info on the improved debugger #538

[activaigor]

@DonJayamanne still extremely slow

[DonJayamanne]

Please could you file a separate issue for performance issues related to the new experimental debugger. This issue has been closed.