Bug 262097

Summary:

REGRESSION (iOS 17): 100x performance degradation of Range.setStart() after repeating DOM operation.

Product:

WebKit

Reporter:

Takao Baba <baba>

Component:

DOM

Assignee:

Nobody <webkit-unassigned>

Status:

NEW

Severity:

Normal

CC:

cdumez, megan_gardner, rniwa, webkit-bug-importer, wenson_hsieh

Priority:

Keywords:

InRadar

Version:

Safari 17

Hardware:

iPhone / iPad

OS:

iOS 17

Attachments:

Description	Flags
testcase	none
result	none
result movie on iPhone 13	none

Takao Baba

Reported 2023-09-25 22:19:44 PDT

Created attachment 467868 [details] testcase # Steps to reproduce 1. Open attached sample.html 2. Wait tens of seconds. # Expected behavior The processing time shown in "h1" tag is stable, about 20-100ms. # Actual behavior On iOS 17 Safari, the processing time is going to be about 10-100 times slower (about 1000-5000ms), after about 20 seconds. The performance is good in first few seconds. # Note The sample repeats creating a range, modifying the DOM and revert them many times. According to the inspector, "Range.setStart()" in "releaseRange()" takes long time. The issue does not occur on iOS 16.2 and Safari Technology Preview 17.0 on macOS.

Attachments
testcase (3.34 KB, text/html) 2023-09-25 22:19 PDT, Takao Baba	no flags	Details
result (184.92 KB, image/png) 2023-09-25 22:20 PDT, Takao Baba	no flags	Details
result movie on iPhone 13 (1.50 MB, video/quicktime) 2023-09-26 18:18 PDT, Takao Baba	no flags	Details
View All Add attachment proposed patch, testcase, etc.

Takao Baba

Comment 1 2023-09-25 22:20:08 PDT

Created attachment 467869 [details] result

Radar WebKit Bug Importer

Comment 2 2023-09-26 09:28:30 PDT

<rdar://problem/116059496>

Alexey Proskuryakov

Comment 3 2023-09-26 11:27:06 PDT

Thank you for the report. FWIW, I cannot reproduce this on an iPhone.

Takao Baba

Comment 4 2023-09-26 18:15:44 PDT

Thank you for the confirmation. In my company, the issue is able to reproduce at least the following environment. - iPhone SE2 iOS 17.0.2 - iPhone 13 iOS 17.0.1 - iPad 9th iPadOS 17.0 - iPad Simulator iPadOS 17.0 on M1 mac mini

Takao Baba

Comment 5 2023-09-26 18:18:32 PDT

Created attachment 467886 [details] result movie on iPhone 13

Note You need to log in before you can comment on or make changes to this bug.