53521 - XUL template with lots of data makes browser unresponsive

Status: NEW

(Core :: XUL, defect, P3)

Description

[Matthew Cline]

Linux build 20000920, Linxu 2.2.14 i686, RedHat 6.1

When looking into the limits of XUL templates, I've found two test
cases where XUL seems to stop working.  Both testcases are based off
of the examples given in
http://www.mozilla.org/docs/xul/xulnotes/template-nested.html

Both examples contain one piece of top level data, with a whole bunch
of sub-level data; the top level data is simply the string "alt",
while each sub-level piece of data is a number (1, 2, 3, ...).  This,
the second example, has 1,000 sub-elements.  While the example with 125
sub-elements only displayed 86 of them, this one displays all 1,000 of
them.  However, this example takes a very long time (about a minute or
more) to become completely ready, during which time the browser becomes
very unresponsive.  While Mozilla is still crunching away, the top level
"alt" is shown, but without the twisty.

(Attachments will be uploaded shortly.)

The first example was givin in bug 53520.

Comment 1

[Matthew Cline]

Attachment: Tescate XUL template

Comment 2

[Matthew Cline]

Attachment: Data for XUL template testcase

Comment 3

[Peter Trudelle]

->waterson

Comment 4

[Chris Waterson]

This is because we have a sucky data structure for nsInMemoryDataSource that
doesn't handle large Sequences well. rjc did a bit of fiddling, so cc'ing him on
the bug.

Comment 5

[Robert John Churchill]

Adding dependancy to bug # 35817 which contains RDF SEQ optimizations.

Comment 6

[BugBot [:suhaib / :marco/ :calixte]]

The bug assignee didn't login in Bugzilla in the last 7 months, so the assignee is being reset.