291654 - Freeze caused by external xml document in xpath expression

Status: RESOLVED EXPIRED

(Core :: XSLT, defect)

Description

[Jamie Thompson]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.7) Gecko/20050414 Firefox/1.0.3
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.7) Gecko/20050414 Firefox/1.0.3

I'm experimenting with xslt, and when I added a stupidly-large background image
(~700KB), I found that loading the page was fine, but refreshing it almost
always locked up Firefox solid. In preperation for filing this bug, I hacked out
as much as I could for a testcase, but found that the large background image was
not the cause. Much fiddling later I found that the single expression that
triggered the freeze was:

select="(document('equipment')|document('equipment/all
equipment.xml'))/equipment/list"

Here I am taking the result of a query and merging it with an extra node set
providing a wildcard, these are then used to populate a select input control. If
either the background image or this expression is removed, no freeze occurs, and
likewise, if I remove the query script and replace it with a static xml file, no
freeze occurs either.

My guess is that the large background image is causing the external document
load to stall, and some kind of timeout issue is arising. Other than that I'm at
a loss as I'm on the same LAN as the server and IE loads it near instantly
everytime.

The url given is the minimal testcase, I was unable to reduce it to a static
example as the time required for the scripts to execute seems to be crucial to
triggering the bug. The orignal page this appeared on is
http://qwerki.jamie-thompson.co.uk/photos/query?query=church but as I am
actively developing that site I cannot vouch for it being usable at any given
time, hence why I made a testcase.

Somewhat accidentally, I discovered that this freeze is not fatal; I left a
frozen instance whilst I made coffee and when I returned it had come back to
life. Waiting instead of killing the process revealed that after a few minutes
of being frozen the browser instance does indeed come back to life.

Reproducible: Always

Steps to Reproduce:
1. Go to the url.
2. Hit refresh several times


Actual Results:  
The browser window freezes for several minutes.

Expected Results:  
Remained responsive whilst loading

I have confirmed this bug with MOOX optimised builds (MMX and SSE) as well as
the standard 1.0.3 official download. I have also confimed that this occurs with
virgin profiles.

Comment 1

[Axel Hecht]

Could you create an http log when such a lock comes up?
http://www.mozilla.org/projects/netlib/http/http-debugging.html

That would tell us what is going on without having to rely on reproducing your
specific timing.

Comment 2

[Jamie Thompson]

Attachment: Trace of Firefox using "NSPR_LOG_MODULES=nsHttp:5,nsSocketTransport:5,nsHostResolver:5"

Here's the trace you requested. I followed the first set of instructions on the
page you linked to, using the environment vars
"NSPR_LOG_MODULES=nsHttp:5,nsSocketTransport:5,nsHostResolver:5".

I took	a scan through but nothing immediately jumped out at me, but given I
know nothing about the underlying code, I doubt it'd know it anyway :)

NOTE: Bugzilla says no to the 600KB log, so I've split it up. This is the first
part.

Comment 3

[Jamie Thompson]

Attachment: Part 2 of the trace

The Sequel to last summer's hit "The Trace, Part 1"

Comment 4

[Jamie Thompson]

Attachment: The final part of the trace

The thrilling conclusion to "The Trace Trilogy"

Comment 5

[Gervase Markham [:gerv]]

This is an automated message, with ID "auto-resolve01".

This bug has had no comments for a long time. Statistically, we have found that
bug reports that have not been confirmed by a second user after three months are
highly unlikely to be the source of a fix to the code.

While your input is very important to us, our resources are limited and so we
are asking for your help in focussing our efforts. If you can still reproduce
this problem in the latest version of the product (see below for how to obtain a
copy) or, for feature requests, if it's not present in the latest version and
you still believe we should implement it, please visit the URL of this bug
(given at the top of this mail) and add a comment to that effect, giving more
reproduction information if you have it.

If it is not a problem any longer, you need take no action. If this bug is not
changed in any way in the next two weeks, it will be automatically resolved.
Thank you for your help in this matter.

The latest beta releases can be obtained from:
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Comment 6

[Gervase Markham [:gerv]]

This bug has been automatically resolved after a period of inactivity (see above
comment). If anyone thinks this is incorrect, they should feel free to reopen it.