RFC: Using Performance panel for Node.js / Deno JavaScript CPU Profiling #2

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

jecfish
Nov 15, 2022

Author: Nancy Li (@lilysjtu2011), Jecelyn Yeen (@jecfish)
Posted: Nov 9, 2022
Status: Complete
Chrome bug tracker: https://crbug.com/1354548

The goal of this RFC is to validate the design with the community, solicit feedback on open questions, and enable experimentation via a non-production-ready prototype included in this proposal.

Complete: This RFC is now complete. See a summary #2 (comment).

Motivation #

Since Chrome 58, the DevTools team set a long-term goal to deprecate the JavaScript Profiler (Profiler tab), and migrate Node.js and Deno developers to use Performance panel for profiling JavaScript CPU performance.

These changes allow users to profile performance consistently with one single entry point - the Performance panel.

Goals #

Profile Node.js / Deno JavaScript CPU performance with Performance panel
- Developers are able to profile JavaScript CPU performance with the Performance panel.
- The Performance panel should display relevant JavaScript CPU information, similar to the Profiler tab.
Minimize impact on the ecosystem
- Overall mental model: developers should be able to apply their existing knowledge to profile JavaScript CPU performance using the Performance panel, with minimal learning curve.

Current state #

Here is the current workflow on profiling JavaScript CPU performance:

Run node --inspect file-name.js or deno --inspect file-name.js (e.g. use this example file)
Open DevTools for Node via one of these options:
- The green Node button at the top of DevTools
- Enter url chrome://inspect > Devices > click Open dedicated DevTools for Node
- Enter url chrome://inspect > Remote target > click Inspect
Start and end profiling by clicking the Record button in the Profiler tab.
View the result in the Profiler tab. Use the dropdown to switch to different views. It support 3 modes currently :
- Chart. Users can switch to the Chart view with the dropdown.
- Heavy (bottom up). This is the default view.
- Tree (top down). Users can switch to the Chart view with the dropdown.
Chart

Heavy (bottom up)

Tree (top down)

Try the prototype: Profile using the Performance panel #

There is a prototype implementation. Below, we show a guide for trying it out. This is a draft implementation, with missing features and non-final design aspects.

Please use Chrome Canary to play with the prototype.

Profiling with the Record button

Run node --inspect file-name.js or deno --inspect file-name.js
Open DevTools for Node. (Chrome Canary)
Open the Performance panel via the 3-dot menu > More tools > Performance panel. This step is not required once the changes are rolled out officially, the Performance panel will show by default.
Start and end profiling by clicking the Record button in the Performance panel.
View the result in the Performance panel. The UI is different from the Profiler tab but you can find all the information:
- Chart. The Performance panel always shows the chart on top.
- Heavy (bottom up). The Performance panel shows this information in the bottom pane > Bottom-up.
- Tree (top down). The Performance panel shows this information in the bottom pane > Call tree.
Chart

Bottom-up

Call tree

Profiling with the console.profile() command

If you profile performance with the console.profile() command, you need to enable an experiment to map the result to the Performance panel.

Enable the View console.profile() results in the Performance panel for Node.js checkbox via the Settings icon > Experiments tab.
Open DevTools for Node. (Chrome Canary)
Run node --inspect file-name.js or deno --inspect file-name.js (e.g. use this example file)
Once the profile is completed, the result will be shown in the Performance panel automatically.

FAQ #

What will happen with the Profiler tab in the future? Will that be deprecated / removed?
Yes, we plan to deprecate the Profiler tab by stages. We will look into community feedback, and implement the JavaScript profiling capability into the Performance panel before deprecation.
Can I load the CPU profile I saved in the Profiler tab previously into the Performance panel?
Yes. You can import .cpuprofile files to the Performance panel.
Are both Profiler tab and Performance panel using the same data source?
Yes. The backend data source is the same for both. However, there are frontend logics that change the displayed data in the Profiler tab.

Below are the same profiling results shown in the Profiler tab and Performance panel.

There are 3 1 known differences at the moment:

a. From showing frames directly to organizing them under call stack - In the above example, the Profiler shows executeUserEntryPoint and the Module frames straight away. On the other hand, the Performance panel organizes them under the same call stack, you need to expand them to view it.
b. crbug.com/1382733 (Fixed) - Some frames like (garbage collector) are hidden now in the Performance panel. We are working on adding them.
c. crbug.com/1080918 (Fixed) - Differences in profiling setTimeout call due to the stack trace collection. We are working on addressing this.
Where is the realtime total JS heap size view?
The realtime Total JS heap size information is already available in the Memory panel. There is no plan to move that into the Performance panel.

The realtime total JS heap size in the Memory panel
Does the Performance panel support reload and record Node.js / Deno performance?
No. This proposal focuses on migrating the existing features in the Profiler tab to the Performance panel. The Profiler tab doesn’t support reload and record.

Questions for Discussion #

In addition to general feedback, we would like to collect feedback on the following specific questions:

Does the prototype correctly display JavaScript profiling information?
We are interested in any cases where the information is missing or has discrepancy with the Profiler tab.
Does profiling in the Performance panel UI work well for you?
We would be interested in any use cases where this change in UI would be problematic or burdensome, and where the UI is important.
For example, should we enlarge the Bottom-up tab and show it by default when you open the Performance panel in Node.js / Deno mode?

You must be logged in to vote

All reactions

hashseed
Nov 16, 2022
Maintainer

@joyeecheung @mhdawson @mcollina @jasnell @gireeshpunathil @Qard FYI

You must be logged in to vote

All reactions

3 replies

Qard Nov 17, 2022

Looks very nice!

You mention there's no plan to move Total JS heap size, but the performance tab includes memory information currently. Is there some technical reason for not moving Total JS heap size too or just a scope concern and could therefore happen separately in the future? I would really like to see a more unified view for that. Something more like macOS Instruments would be really nice where you could pick which profilers to activate and it will capture and visualize them all together.

All reactions

lilysjtu2011 Nov 21, 2022

Hi @Qard , the total JS heap size in the RFC referring to the real time total JS heaps size view (as highlighted below).

We don’t plan to migrate that to the Performance panel because the Memory panel has a similar UI for that.

Are you referring to another “Total JS heap size” or you would like to see this information in the Performance panel?

All reactions

Qard Nov 21, 2022

Yes, that's what I was referring to. The Performance tab has a checkbox for memory and I'm unclear what, if anything, is stopping the existing memory tab data from being ported into that.

All reactions

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

jecfish
Nov 16, 2022
Author

@jrieken @bartlomieju fyi

You must be logged in to vote

All reactions

0 replies

gireeshpunathil
Nov 17, 2022

@RafaelGSS fyi

You must be logged in to vote

All reactions

0 replies

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

joyeecheung
Nov 17, 2022

Nice write-up of the new performance panel! I am wondering, is the Node.js-dedicated panel going to remain in chrome://inspect?

Also, I gave it a try and profiled a typical HTTP server:

'use strict';

const http = require('http');
const bodyLength = 12345;

const body = 'c'.repeat(bodyLength);
const server = http.createServer(function(req, res) {
  res.writeHead(200, {
    'Content-Length': bodyLength,
    'Content-Type': 'text/plain'
  });
  res.end(body);
});
server.listen(0, '127.0.0.1', () => {
  const { address, port } = server.address();
  console.log(`http://${address}:${port}`);
});

And profiled it with:

$ autocannon -d 10 http://127.0.0.1:$PORT

Here is the comparison (the workload in the particular span that the profile is taken differed slightly so minor differences in the calculations can be ignored):

The call trees:

The bottom-ups:

Close-up looks of some frames:

Other than the (garbage collector) entries missing, as already mentioned in the OP, there are some noticeable differences:

(idle) is missing
(program) is missing - like (idle) or (garbage collector) this is actually in the inspector protocol response.
There is now a Function call entry, is there some documentation about what that is? It looks like some sort of "native-calling-back-to-JS trampoline" entry.
I can see in the summary that there are System and Idle entries in the chart, but they are quite different from the calculations in the profiler panel - AFAIK the calculations from the profiler panel are correct (if we replace System with program, which in V8 means a combination of EXTERNAL (embedder) + PARSER + COMPILER and a few other VM states in the "system").
It is now possible to see the call trees and bottom-ups of a specific span, which is pretty nice 👍
When I saved the profile from the performance panel, the resulted file is named Profile-<timestamp>.json, from the profiler panel it's CPU-<timestamp>.cpuprofile. The JSON saved from the performance panel is in a format different from the JSON-formatted response from the inspector protocol (that is, https://chromedevtools.github.io/devtools-protocol/tot/Profiler/#type-Profile). There are some external tools that analyzes the profile using the inspector protocol format, so to fully replace the original panel it would be nice to be able to save the profile in that format, maybe after answering a prompt before saving.

You must be logged in to vote

All reactions

3 replies

lilysjtu2011 Nov 21, 2022

Hi Joyee, for your first question not sure if I understand your question correctly. Do you mean if we will remove the link in chrome://inspect? (See the image below)

The “Open dedicated DevTools for Node” link will remain showing. However, instead of showing the Profiler tab when clicked, it will show the Performance panel instead.

The Profiler tab will be removed in the future.

All reactions

lilysjtu2011 Nov 21, 2022

For your detailed feedback, here are my replies:

Q1 & Q2: Missing (idle)(program) entries

These missing entries are caused by the same reason as (garbage collector). We are currently working on it. Here is the tracking bug crbug.com/1382733.

We will update again when the bug is fixed!

Q3: The Function call entry

After some investigation, this is actually related to Q1 & Q2 crbug.com/1382733. After the bug fix, the Function call should be gone.

Q4: Incorrect calculation in `System` and `Idle` calculations in the Performance panel’s Summary tab

We’ve opened a bug crbug.com/1392436 for this. I will investigate this further.

Q5: Ability to view Call tree and Bottom-ups on a specific span

Good to know. Thank you.

Q6: Options to download .cpuprofile from the Performance panel

Nice feature request. Created a new feature request crbug.com/1392446 to track this.

All reactions

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

lilysjtu2011 Jan 2, 2023

Hey @joyeecheung , some updates here.

The Performance panel is updated so the system nodes like (idle), (garbage collector) and (program) are no longer missing. Also the time calculation is also corrected now.
And for downloading, you can now download .cpuprofile when you use the Performance panel for Node.js.

Please take a look at the updates and feedback is welcomed :)
Thanks

All reactions

mcollina
Nov 18, 2022

A use case I have been using is to collect CPU and memory profiles using the inspector API directly and then loading them up in chrome to visualize them. Given the format has changed, will this still be supported?

You must be logged in to vote

All reactions

2 replies

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

jrieken Nov 18, 2022

Same here. In VS Code we automatically perform CPU profiling and analyse its data. For that we use Profiler.start and Profiler.end command (from https://chromedevtools.github.io/devtools-protocol/tot/Profiler/). So, is this a UX only change or will the Profiler also disappear from the devtools-protocol?

All reactions

hashseed Nov 18, 2022
Maintainer

CDP is not going to be affected. We are talking about replacing one consumer of the protocol with another consumer, for the Node.js use case.

All reactions

Qard
Nov 18, 2022

Seems to not handle large profiles as well as the old Profiler tab. I opened a ~25mb profile in the Profiler tab which loaded and displayed fine and could be navigated relatively smoothly with only a little bit of lag. I loaded the same profile in the Performance tab and it seemed to lock up while loading, eventually displaying the thing after several minutes. When I tried to click anything in the chart visualization it crashed the whole browser. 😬

You must be logged in to vote

All reactions

5 replies

jecfish Nov 21, 2022
Author

Thanks Stephen, created a crbug.com/1391853 for @lilysjtu2011 to follow up.

All reactions

Qard Nov 21, 2022

Thanks. I added a comment that I can share the profile data with V8 folks if they want to investigate that profile specifically. 😄

All reactions

hashseed Nov 21, 2022
Maintainer

It's not actually V8 folks, but DevTools folks working on this.

So if you can share your profile with e.g. jec@google.com, we might use the Performance panel on the Performance panel so that we can profile the performance of the Performance panel loading your performance profile.

😄

All reactions

jecfish Nov 21, 2022
Author

Hah, before this message, I've dropped @Qard a follow up email with @lilysjtu2011. :)

All reactions

Qard Nov 22, 2022

Sorry, that's what I meant, devtools folks, the V8-adjacent. 😅

In any case, I sent the profile along already. Hopefully that proves helpful in improving the performance. 🙂

All reactions

bartlomieju
Nov 20, 2022

Hi @jecfish, I'm gonna need one or two more days to provide my feedback - thanks to your example I discovered that Deno's console implementation if missing some console methods that should be available in the inspector.

You must be logged in to vote

All reactions

0 replies

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

jecfish
Jan 3, 2023
Author

Hi all,

Happy New Year! Thanks for your testing and feedback. @lilysjtu2011 has made a couple of significant improvements based on your feedback.

Please give it another round of test in Canary and comment!

Below are the improvements:

Added options to download .cpuprofile from the Performance panel - crbug.com/1392446
Included missing events (e.g. (program), (idle), (garbage collector)) in the Performance panel - crbug.com/1382733
Fixed deviation in System and Idle calculation - crbug.com/1392436
Fixed inaccurate (amplified) setTimeout calls in performance profiles - crbug.com/1080918
[Reporter mentioned not reproduce-able, Let us know if you face this issue] Not handle large profiles well in the Performance panel - crbug.com/1391853

Looking forward to your feedback on this new workflow!

You must be logged in to vote

All reactions

0 replies

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

jecfish
Mar 3, 2023
Author

Hi all,

We appreciate your valuable testing and feedback thus far. With all blocking issues addressed, we are currently in the process of deprecating the JS Profiler, which involves 4 stages:

In Chrome 112, we will display a warning banner in the JS Profiler. Please share any feedback you have in this RFC.
In Chrome 113, we will disable the tab. However, you will still be able to turn it on temporarily. To provide feedback, please visit crbug.com/1354548.
In Chrome 114, the tab will be hidden by default. But you can still turn it on temporarily using a flag. Feedback can be shared via crbug.com/1354548.
Finally, in Chrome 115 or later, we will completely remove the JS Profiler once all blocking issues have been resolved.

If you come across any issues during this process, please do report them to us.

Regards,
Nancy & Jecelyn

You must be logged in to vote

All reactions

0 replies

stoem
Apr 14, 2023

The old JS Profiler allows fairly easy access to the most time consuming functions and even lines of code.
The same tasks seems much trickier in the Performance Panel - can you point out how we'd achieve narrowing down any performance bottlenecks back to the file/function/line of code that causes it using the Performance Panel?

You must be logged in to vote

All reactions

1 reply

lilysjtu2011 Jun 23, 2023

Hi @stoem , you can check here:

The Heavy (Bottom Up) tab in JS profiler is now Bottom-up, and Tree (Top Down) is now Call tree

All reactions

realyze
Apr 17, 2023

There's two things I would sorely miss if we deprecate JS profiler:

If I understand correctly, the Profiler tab only shows information for the selected task, no? What I very often do is that I record an interaction (e.g. dragging or typing) in the JS Profiler tab and then look at total CPU time spent running a give method. The execution time varies between tasks so it's super useful to be able to see total time spent, not just time spent within selected task.
The JS profiler tab is much faster. For a long complex profile, it can take tens of seconds before the Profiler tab lets me select any task without deselecting it immediately (possibly a profiler bug?)

You must be logged in to vote

All reactions

1 reply

lilysjtu2011 Jun 23, 2023

Hi @realyze ,
For 1, can you give me more information? You can see the total time in the Bottom-Up or Call Tree in the bottom drawer. Don't know if this is what you are finding.
For 2, we are working on improve the speed. Some track bug is here: crbug.com/1457639

All reactions

o0x2a
Apr 18, 2023

How to select a VM instance in Performance panel? Currently it is possible to select an iframe or web-worker in Profile tab.

You must be logged in to vote

All reactions

3 replies

lilysjtu2011 Jul 19, 2023

Hi @o0x2a , I don't know if you are using the Profile tab for web app or Node app. In the Performance panel, we currently will automatically capture JS profiles of all JS isolates, and web workers and Out-of-Process iframes are shown in different tracks. Can you provide more information to me?
Thanks

All reactions

tophf Dec 14, 2023

@lilysjtu2011, the point is to allow us to select the isolate (the worker), which is essential when there are many isolates/frames that we don't want to profile.

All reactions

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

jecfish Dec 15, 2023
Author

Open a bug to track the investigation: crbug.com/1511813

All reactions

aspin
Apr 20, 2023

Are there any types of targets that aren't supported by the Performance panel that are by the older Profiler tab? Currently, the profiler tab works for me, but when I try to record a profile in the Performance panel I get "Performance trace recording not supported by this type of target".

You must be logged in to vote

All reactions

5 replies

lilysjtu2011 Jun 23, 2023

Hi @aspin ,
In Performance panel we also support tracing. Can you give me more information about how you use the Performance panel, and on which target you tried to record the profile?
Thanks

All reactions

aspin Jul 14, 2023

unfortunately I don't have access to the codebase anymore, but it wasn't anything particular complex. I started a node16 app, enabled the debugger and tried to connect to it with the performance panel, and nothing would work. The old profiler connected fine.

All reactions

lilysjtu2011 Jul 19, 2023

Thanks for the reply, I will try to repro and see if i can get some more information

All reactions

jecfish Dec 14, 2023
Author

Opened a bug for further investigation: https://crbug.com/1511486

All reactions

and-oli Dec 14, 2023

Hi @aspin. As with some of the other threads, we have landed a good amount of fixes to the Performance panel that tackle issues like the one you described so, could we please ask you to confirm if the issue persists today?. The latest improvements are shipping from Chrome version 121.0.6167.16 (currently Chrome Beta), so I suggest testing using this. Thanks!

All reactions

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

suzmas
May 23, 2023

The Performance tab is significantly slower (as previously noted #2 (comment)), consumes a ton of CPU for complex profiles, and yesterday it crashed several times while trying to load the output from a fairly long-running profile - I couldn't even download the profile before the Performance tab became unresponsive, so I had to re-run it and take small (sub 90s) profiles multiple times, for the duration of the task. That is, of course, very inconvenient - re-enabled the Profiler tab because of this.

You must be logged in to vote

All reactions

1 reply

lilysjtu2011 Jun 23, 2023

Hi @suzmas , thanks for your feedback, we are now working on improve the speed. Some track bug is here: crbug.com/1457639.
Will update here when we have more progress. Thanks

All reactions

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

Eric-Gurt
Jun 20, 2023

JS Profiler works on big projects (games) no matter how long you profile it for.

Performance tab just dies after you stop it past more than 5 seconds of profiling within same project (without screenshots or anything else pretty much).

But interestingly profiling with JS Profiler and then exporting/importing same file via Performance tab does work fine too.

You must be logged in to vote

All reactions

5 replies

lilysjtu2011 Jun 23, 2023

Hi @Eric-Gurt , thanks for your feedback. Can you give more information how you profile the code, and if possible some code example will be helpful.
Thanks

All reactions

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

Eric-Gurt Jul 14, 2023

This only happens in a big project which I'm not able to share right now. It includes lots of JS files (loaded dynamically), lots of different (usually sealed) objects, huge arrays, THREE.js, canvas-generated textures, geometry manipulations, DataView-s, lots of strings. There is like 21 MB of just JavaScript files.

I just tried to test it with Performance tab and ~15 seconds of recording has been decoded in approximately 1 minute.

And then after tab close and reopening same scenario with JavaScript Profiler tab only took 2-3 seconds after recording was stopped.

So I pressed Ctrl + I on the DevTools for page and right before I stopped Performance tab recording I started profiling this DevTools for page with "JavaScript Profiler" tab... I've got some useful results perhaps?

This is in Edge:
screenshot
.cpuprofile

This is in Chrome. It is just my project isn't fully configured for it. Yet still take 20 seconds to show results in Performance tab when it takes nothing when done with JavaScript Profiler:
screenshot
.cpuprofile

It seems to be proportional to the amount of stuff done by JavaScript on a page (Chrome's case is loading JS files dynamically, does a few requests then show simple THREE.js scene and that is pretty much all it does).

All reactions

lilysjtu2011 Jul 19, 2023

Thanks for the reply, I will take a look on this.

All reactions

jecfish Dec 14, 2023
Author

Open a bug to track the investigation: https://crbug.com/1511491

All reactions

and-oli Dec 14, 2023

Hi @Eric-Gurt. Could we please ask you to confirm if the issue persists today? We have landed a good amount of fixes to the Performance panel that tackle issues like the one you described. The latest speed improvements are shipping from Chrome version 121.0.6167.16 (currently Chrome Beta), so I suggest testing using this. Thanks!

All reactions

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

ajuni880
Jul 7, 2023

Hi, I am trying to debug a node application it used to work fine with JS Profiler but with Performance tab it just dies after couple of seconds. Also when starting the profiling in performance tab it stops the task initiated with node inspect-brk. Stopping manually the profiling shows this screen and it stays here forever.

Chrome Version 114.0.5735.199 (Official Build) (64-bit)

You must be logged in to vote

All reactions

7 replies

ajuni880 Jul 17, 2023

Hi @lilysjtu2011, there is no other message, the file is not that big, it's a jest file with angular tests. I can't download the cpuprofile because devtools hangs up.

All reactions

lilysjtu2011 Jul 19, 2023

Thanks for the reply, I will try to check this.

All reactions

jecfish Dec 14, 2023
Author

Open a bug report to track the investigation: https://crbug.com/1511489

All reactions

and-oli Dec 14, 2023

Hi @ajuni880, sorry for jumping so late to the discussion. We have recently worked on improving the support for node profiling use cases in the Performance Panel. As such, I would expect your use case to work fine now on the latest Chrome Stable version. Could we please ask you to confirm if the issue you describe has been fixed? Thanks!

All reactions

and-oli Dec 14, 2023

I forgot to mention: the latest Chrome Stable version I was talking about is 120.0.6099.71 (Official Build). Here the Performance Panel should be able to load CPU profiles. However, the latest speed improvements are shipping from version 121.0.6167.16 (currently on Beta), so I suggest testing using this latter.

All reactions

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

tophf
Dec 14, 2023

The old profiler immediately opens the linked source code when you click a block in the flamechart.
It'd be nice to have the same via double-click or Ctrl-click or right-click menu in the new profiler.

Currently we have to separately click the source link in the bottom drawer, which is pretty far from the flamechart, and if we switch the tab in the drawer to investigate the block we'll have to return to the Summary tab again, constantly switching tabs is inconvenient.

You must be logged in to vote

All reactions

1 reply

{{editor}}'s edit

{{actor}} deleted this content .

{{editor}}'s edit

jecfish Dec 15, 2023
Author

Open a bug to track the investigation: crbug.com/1511814

All reactions

jecfish
Dec 15, 2023
Author

After almost a year of discussion, we're closing the RFC for using the Performance panel for Node.js/Deno JavaScript CPU profiling.

As previously communicated, we're currently in stage 3 of the 4-stage JS Profiler deprecation. In upcoming releases, we'll remove the JS Profiler entirely once all blocking issues are resolved.

Blocking Issues

Performance. We’ve fixed the major performance issue that is blocking you. From our benchmark, The speed has improved significantly in the Performance panel. For example, the initial loading time for a 48m file, dropped from 10s to 2s. Please give it a spin and let us know! (crbug.com/1457639)
Profile selected VM instance. We understand that the JS Profiler allows you to select the VM instance for profiling. We're actively working on implementing it within the Performance panel before the final removal of the JS Profiler. (crbug.com/1511813)

Follow ups

There are other UX improvement suggestions as well, we’ll consider adding them, possibly in follow-up releases.

If you have any questions or feedback, please share them at crbug.com/1354548.

We would like to thank everyone for your feedback and for your help in shaping Chrome DevTools!

You must be logged in to vote

All reactions

0 replies

RFC: Using Performance panel for Node.js / Deno JavaScript CPU Profiling · ChromeDevTools/rfcs · Discussion #2 · GitHub

Uh oh!

RFC: Using Performance panel for Node.js / Deno JavaScript CPU Profiling #2

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{editor}}'s edit

{{editor}}'s edit

Uh oh!

Motivation #

Goals #

Current state #

Try the prototype: Profile using the Performance panel #

Profiling with the Record button

Profiling with the console.profile() command

FAQ #

Questions for Discussion #

Replies: 18 comments · 37 replies

Uh oh!

{{title}}

Uh oh!

hashseed Nov 16, 2022 Maintainer

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{editor}}'s edit

{{editor}}'s edit

Uh oh!

jecfish Nov 16, 2022 Author

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{editor}}'s edit

{{editor}}'s edit

Uh oh!

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{editor}}'s edit

{{editor}}'s edit

Uh oh!

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{title}}

Uh oh!

Uh oh!

{{editor}}'s edit

{{editor}}'s edit

Uh oh!

Uh oh!

{{title}}

Uh oh!

hashseed Nov 18, 2022 Maintainer

Uh oh!

{{title}}

Uh oh!

Replies: 18 comments 37 replies

hashseed
Nov 16, 2022
Maintainer

jecfish
Nov 16, 2022
Author

hashseed Nov 18, 2022
Maintainer

jecfish Nov 21, 2022
Author

hashseed Nov 21, 2022
Maintainer

jecfish Nov 21, 2022
Author

jecfish
Jan 3, 2023
Author

jecfish
Mar 3, 2023
Author