1547302 - ES modules load very slowly

Status: RESOLVED INVALID

(Core :: IPC, defect)

Description

[709922234]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:68.0) Gecko/20100101 Firefox/68.0

Steps to reproduce:

1. open https://xianqiao.wang/test/esm/public/es6-modules.html
2. open web console
3. view output

Expected results:

The output is a small number, result similar to https://xianqiao.wang/test/esm/public/webpack-modules.html

Comment 1

[Timea Cernea [:tbabos][inactive]]

Reproduced the issue on all latest Firefox versions on Mac OS 10.14:

Nightly:
actual: 3619ms
expected: 84ms

Beta:
actual: 5400ms
expected: 1186ms

Release:
actual: 9832ms
expected: 1292ms

Moving this over to a component so developers can take a look at it. Thanks for the report!

Comment 2

[Nicolas B. Pierron [:nbp] {back on 17/11}]

Win 10 ARM64: https://perfht.ml/2ZQuIzP

Looking at the profile, the content process seems to spend most of its time waiting rather than processing anything.
However the parent process seems to be handling events quite late and not giving any information to the child process fast enough.

I have no idea which category this bug should be filed against, but it definitely does not look like we are waiting on JS completion.
Timea, any idea where this bug should go based on the profile?

Comment 3

[Timea Cernea [:tbabos][inactive]]

Tentatively moving this over to DOM:Events, not sure about it tho, I don't have the knowledge to understand performance profiles :(
Blind shooting the statement "seems to be handling events quite late".

Comment 4

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Maybe IPC?

Comment 5

[709922234]

https://bugs.chromium.org/p/chromium/issues/detail?id=957099#c4

Comment 6

[Olli Pettay [:smaug][[e-mail]]]

Nothing unexpected there. Tons of scripts being loaded.