karma-chrome-launcher
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Tests are running slower on the launched chrome browser
Summary
Tests are running slower on the launched chrome browser
Steps to reproduce
- git clone https://github.com/pluralsight-projects/SampleKarmaJasmineProject.git
- Run
yarn && yarn run test
- By default, it is configured to launch the Chrome browser. There are only three tests and it takes greater than one second in the newly launched chrome.
- Now switch the launcher to Firefox by replacing
karma-chrome-launcher
tokarma-firefox-launcher
inpackage.json
. Similarly, inkarma.conf.js
, replacekarma-chrome-launcher
inplugins
withkarma-firefox-launcher
and replacebrowsers
fromChrome
toFirefox
. - Run
yarn && yarn run test
. It will launch Firefox now and the tests run way faster than chrome.
Description
KarmaJS internally spawns the browser in a child process along with a custom user-data-dir
I observed that on spawned chrome (with a custom user-data-dir), the tests are running very slow as compared to other browsers like Firefox.
I have validated the same by running other test runner such as TestemJS which also spawns the chrome with custom user-data-dir.
In the attached screenshots, you can see that on chrome it is taking around 2 seconds to run the tests where as on Firefox it takes less than 200ms.
I also observed that as more and more tests start running, spawned chrome catches up the speed but falls short (even after catching up) compared to running the tests on non-spawned chrome.
I raised a ticket on the chromium team as well for the same https://bugs.chromium.org/p/chromium/issues/detail?id=1406168
I'm raising this ticket here as well so that others will be aware of this issue.
Screenshots
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Quick thought: could this be related to #217 ??
I was having the same issue when using node 14.20x, with node 16.x this does not happen to me.
"karma": "~6.4.1", "karma-chrome-launcher": "~3.2.0"
Quick thought: could this be related to #217 ??
I tried with '--disable-ipc-flooding-protection'
and seeing the same result of slow running tests.
I was having the same issue when using node 14.20x, with node 16.x this does not happen to me.
"karma": "~6.4.1", "karma-chrome-launcher": "~3.2.0"
@lferreira07 I'm also on 16.x version of node and still running into the issue. I believe it has something to do with the chromium browser rather than the node version.