ng serve uses a lot of CPU % #2748

areijngoudt · 2016-10-17T14:12:42Z

Mac OSX El Capitan

Versions.

angular-cli: 1.0.0-beta.17
node: 5.7.1
os: darwin x64

angular-cli uses about 85% CPU when I only use ng serve during development, also when I'n not changing code but just use the webapp in a browser.

kylecordes · 2016-10-17T20:59:43Z

I experienced the same thing here. Sitting idle, with nothing changing, approximately one CPU core burns 100% in ng serve. Latest node, latest OSX, CLI beta 17.

mseemann · 2016-10-17T21:20:31Z

npm i fsevents should solve this.

masaanli · 2016-10-18T10:54:18Z

Not working on Windows.

areijngoudt · 2016-10-31T07:34:51Z

installing fsevents solves this issue on mac. Thanks @mseemann

rryter · 2016-10-31T08:02:41Z

I don't think this issue should be closed. Manually installing fsevents can not be the longterm solution.

benyaminshoham · 2017-03-01T10:56:56Z

Does it make sense to add fsevents to the dependencies of @angular/cli?

msnatu · 2017-04-04T18:01:20Z

@mseemann Thanks a lot!

jlberrocal · 2017-06-07T14:38:24Z

fsevents only work for mac, but what about windows and linux, in my case what is literally eating is my ram, ng process consumes 1.2GB which i consider a lot for a process like that one

JohannesRudolph · 2017-06-07T16:57:55Z

Jose, please keep in mind that node is GC'd so it will happily use available memory and won't collect aggressively until pressured by the OS which doesn't happen if you have a lot of RAM ;-) So unless ng is eating all your memory and your OS starts paging other stuff you should be fine.

…

On Wed, Jun 7, 2017 at 5:38 PM, Jose Berrocal ***@***.***> wrote: fsevents only work for mac, but what about windows and linux, in my case what is literally eating is my ram, ng process consumes 1.2GB which i consider a lot for a process like that one — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#2748 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAH8N0Lg5SAAoyQVRdvVPBVsaZNKX8wiks5sBrX2gaJpZM4KYq8B> .

Almenon · 2017-09-22T03:07:23Z

have you tried using task manager to lower the affinity / priority of the process?

chestercharles · 2017-11-15T17:00:04Z

@Almenon 's solution to lower the affinity/priority of the process has been working for me. However, it is kinda tedious to do every time I run ng serve.

If I don't manually lower the affinity/priority of the process, my CPU usage is at 99%.

Running on windows 8

trumbitta · 2017-11-27T11:36:23Z

@rryter also, if I add it to my package.json every build not happening under Mac OS will fail:

npm ERR! notsup Unsupported platform for [email protected]: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})

trumbitta · 2017-11-27T14:32:12Z

I ended up adding the following little script to my postinstall:

const isMac = /^darwin/.test(process.platform);

if (isMac === true) {
  const process = require('child_process');
  process.execSync('npm install fsevents --no-save');
}

rightisleft · 2017-12-07T00:33:20Z

Running under debian, using the ng serve --poll command causes my cpu to spike to %300 (3coresx100)

smallg · 2018-03-29T13:12:15Z

this is very useful

azcdev · 2018-05-12T18:48:50Z

Can somebody explain why fsevents solves this issue? Posting a solution without an explanation isn't helpful.

sonjaerock · 2018-05-31T07:37:15Z

What is solution on linux ?

PyroSA · 2018-06-05T15:30:35Z

@alanchavez88 fsevents allows the process to subscribe to File System EVENTS.

I can only assume angular-cli has logic built in that makes use of this if it's available.

This means that angular-cli no longer has to poll the actual files to see if changes occurred, it simply waits for OSX to notify it of a file change.

EDIT: Just to confirm, fsevents calmed down my CPU as well. No more hand-warmer.

electrichead · 2018-06-09T16:48:34Z

@alanchavez88 further to @PyroSA reply: it might have to do with chokidar, which is used by karma and the @angular/compiler-cli for watching files for changes. Chokidar is a wrapper around different ways to watch for files and fsevents is one of those. Chokidar has fsevents as an optional dependency - if it's present it will use it otherwise it has fallbacks. So if nothing else installs fsevents, chokidar goes with one of the alternatives and that eats up CPU because of polling.

https://www.npmjs.com/package/chokidar#performance

You can add "fsevents" to "optionalDependencies" in package.json to persist this change.

pattersongp · 2018-07-06T14:28:11Z

For anyone running on Linux, I've been running my build and serve with a lower priority. It's really helped with ng hogging the CPU.

You can try:
$ nice -10 ng <build, search> --watch true or poll N which appears to do the trick.

This should also work on other *NIX OS's

PyroSA · 2018-07-06T16:52:20Z

Increasing the polling interval is enough to calm down the watching and will work even on non *nix.

I helped our Windows guys with their overeager virus scanners in the past.

tebantebanteban · 2018-07-31T15:41:21Z

same issue here

Angular CLI: 6.1.1
Node: 10.7.0
OS: darwin x64
Angular: 6.1.0
... animations, common, compiler, compiler-cli, core, forms
... http, language-service, platform-browser
... platform-browser-dynamic, platform-server, router

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.6.8
@angular-devkit/build-angular     0.6.8
@angular-devkit/build-optimizer   0.6.8
@angular-devkit/core              0.6.8
@angular-devkit/schematics        0.7.1
@angular/cli                      6.1.1
@ngtools/webpack                  6.0.8
@schematics/angular               0.7.1
@schematics/update                0.7.1
rxjs                              6.2.2
typescript                        2.7.2
webpack                           4.8.3

ryansigg · 2018-08-24T16:02:42Z

Still seems to be an issue with CLI v 5.0.0.

Fixed with fsevents.
My ng process CPU usage went from 80-100% all the time down to a max of 8% only while compiling otherwise it's at 0 as expected.

grantlucas · 2018-09-19T13:02:30Z

This is still definitely an issue on linux in CLI 6.2.2

Angular CLI: 6.2.2
Node: 8.12.0
OS: linux x64
Angular: 6.1.7
... animations, common, compiler, compiler-cli, core, forms
... http, language-service, platform-browser
... platform-browser-dynamic, router

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.8.2
@angular-devkit/build-angular     0.8.2
@angular-devkit/build-optimizer   0.8.2
@angular-devkit/build-webpack     0.8.2
@angular-devkit/core              0.8.2
@angular-devkit/schematics        0.8.2
@angular/cli                      6.2.2
@ngtools/webpack                  6.2.2
@schematics/angular               0.8.2
@schematics/update                0.8.2
rxjs                              6.3.2
typescript                        2.9.2
webpack                           4.19.1

This is a major issue when running within a Vagrant machine for example. When I run this on my host machine (OSX) everything if fine with fsevents, but using poll in linux on the VM, both cores will steadily be at 80-90%+ usage.

grantlucas · 2018-09-19T13:04:16Z

@filipesilva Any chance at getting this issue re-opened? It still seems to be an issue.

I had experienced it a few months ago on an older version of CLI and Angular but just finished doing a complete upgrade in the hopes this issue would be resolved in later versions. Sadly it is not.

grantlucas · 2018-09-19T13:18:53Z

In my other custom Webpack configs for other watchers, I normally have

        watchOptions: {
            ignored: /node_modules/,
            aggregateTimeout: 300,
            poll: 1000
        },

and that works great within Vagrant, without much CPU usage. Based on what I'm seeing in this repo when searching for watchOptions, I only ever see the poll flag set, nothing for ignored. Is it possible it's trying to watch the whole node_modules folder as well resulting in high CPU usage?

grantlucas · 2018-09-19T18:11:03Z

With some local exploration, I've found that adding the following to the watchOptions in the common webpack config resolved CPU usage issues in a Vagrant setup and allowed or 1 second polling without high CPU usage.

packages/angular_devkit/build_angular/src/angular-cli-files/models/webpack-configs/common.ts#L264

        watchOptions: {
            ignored: /node_modules/,
            aggregateTimeout: 300,
            poll: buildOptions.poll
        },

With that, instead of adding more flags for what to put into watchOptions, it'd be great to be able to specify the whole watch options block instead of just the poll option. Just in case this causes issues for other setups.

I can look into setting up a PR but it may take a while as I familiarize myself with the process for this project.

grantlucas · 2018-09-19T20:41:08Z

Hopefully the ignored flag can be exposed via #12313

angular-automatic-lock-bot · 2019-09-09T01:41:33Z

This issue has been automatically locked due to inactivity.
Please file a new issue if you are encountering a similar or related problem.

Read more about our automatic conversation locking policy.

_{This action has been performed automatically by a bot.}

filipesilva added command: serve needs: investigation Requires some digging to determine if action is needed labels Oct 17, 2016

areijngoudt closed this as completed Oct 31, 2016

rightisleft mentioned this issue Apr 11, 2018

webpack live reload is not working. #1610

Closed

angular-automatic-lock-bot bot locked and limited conversation to collaborators Sep 9, 2019

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

ng serve uses a lot of CPU % #2748

ng serve uses a lot of CPU % #2748

areijngoudt commented Oct 17, 2016

kylecordes commented Oct 17, 2016

mseemann commented Oct 17, 2016

masaanli commented Oct 18, 2016

areijngoudt commented Oct 31, 2016

rryter commented Oct 31, 2016

benyaminshoham commented Mar 1, 2017

msnatu commented Apr 4, 2017

jlberrocal commented Jun 7, 2017

JohannesRudolph commented Jun 7, 2017 via email

Almenon commented Sep 22, 2017

chestercharles commented Nov 15, 2017 •

edited

Loading

trumbitta commented Nov 27, 2017

trumbitta commented Nov 27, 2017

rightisleft commented Dec 7, 2017 •

edited

Loading

smallg commented Mar 29, 2018

azcdev commented May 12, 2018

sonjaerock commented May 31, 2018

PyroSA commented Jun 5, 2018 •

edited

Loading

electrichead commented Jun 9, 2018 •

edited

Loading

pattersongp commented Jul 6, 2018

PyroSA commented Jul 6, 2018

tebantebanteban commented Jul 31, 2018

ryansigg commented Aug 24, 2018

grantlucas commented Sep 19, 2018

grantlucas commented Sep 19, 2018 •

edited

Loading

grantlucas commented Sep 19, 2018

grantlucas commented Sep 19, 2018

grantlucas commented Sep 19, 2018

angular-automatic-lock-bot bot commented Sep 9, 2019

ng serve uses a lot of CPU % #2748

ng serve uses a lot of CPU % #2748

Comments

areijngoudt commented Oct 17, 2016

Versions.

kylecordes commented Oct 17, 2016

mseemann commented Oct 17, 2016

masaanli commented Oct 18, 2016

areijngoudt commented Oct 31, 2016

rryter commented Oct 31, 2016

benyaminshoham commented Mar 1, 2017

msnatu commented Apr 4, 2017

jlberrocal commented Jun 7, 2017

JohannesRudolph commented Jun 7, 2017 via email

Almenon commented Sep 22, 2017

chestercharles commented Nov 15, 2017 • edited Loading

trumbitta commented Nov 27, 2017

trumbitta commented Nov 27, 2017

rightisleft commented Dec 7, 2017 • edited Loading

smallg commented Mar 29, 2018

azcdev commented May 12, 2018

sonjaerock commented May 31, 2018

PyroSA commented Jun 5, 2018 • edited Loading

electrichead commented Jun 9, 2018 • edited Loading

pattersongp commented Jul 6, 2018

PyroSA commented Jul 6, 2018

tebantebanteban commented Jul 31, 2018

ryansigg commented Aug 24, 2018

grantlucas commented Sep 19, 2018

grantlucas commented Sep 19, 2018 • edited Loading

grantlucas commented Sep 19, 2018

grantlucas commented Sep 19, 2018

grantlucas commented Sep 19, 2018

angular-automatic-lock-bot bot commented Sep 9, 2019

chestercharles commented Nov 15, 2017 •

edited

Loading

rightisleft commented Dec 7, 2017 •

edited

Loading

PyroSA commented Jun 5, 2018 •

edited

Loading

electrichead commented Jun 9, 2018 •

edited

Loading

grantlucas commented Sep 19, 2018 •

edited

Loading