459544 - CPU goes to very high if there are some javascript timers in the web page that updating some text fields in the page.

Status: RESOLVED INCOMPLETE

(Core :: JavaScript Engine, defect)

Description

[Andrea]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; it; rv:1.9.0.3) Gecko/2008092416 Firefox/3.0.3
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; it; rv:1.9.0.3) Gecko/2008092416 Firefox/3.0.3

In the travian website (registration needed www.travian.it every game server) all pages contain almost one javascript timer that update text fields in the page, when FF3 load one of these pages the CPU goes high.
With 9 timer in a page, If I execute the "top" command in a shell window, I can see that X server process goes to 87% of CPU loading. The problem is more evident if I use a greasemonkey script that add some timer in the page, in this case the CPU still to 100% for every second.
I have tried to visit Travian website with Opera browser and it work fine.
Windows version of FF3 also work fine, apparently the problem is only in the Linux version.
If I change tab for visiting another website, the CPU Loading goes to low but when i return to travian tab the CPU loading return high.

Reproducible: Always

Steps to Reproduce:
1. Login in a Travian game server
2. Navigate and look CPU loading
3. install greasemonkey
4. install script at address: http://userscripts.org/scripts/show/15943
5. re-login in a Travian game server
6. navigate and look CPU loading.
7. open new tab
8. goes to another wesite by new tab
9. look that CPU loading goes to near only 1%.
10. return to travian tab the CPU loading return to original high value.
Actual Results:  
Every javascript timer present in the page aggravate the CPU condition, with 9 timer for example my CPU goes to 87%.

Expected Results:  
The CPU loading should be not goes high but remain low as in windows version of FF3.

I think that the timer isn't the real problem but I can't verify it... I think that the problem is the dynamic update of the page under timer control because is the X server process that goes to high CPU level and not FF3 process, but this bug is only with firefox while with Opera browser all work fine.

Comment 1

[Wayne Mery (:wsmwk)]

Andrea, 
Can you still reproduce this?

Comment 2

[Firefox Bug Husbandry Bot]

2019-03-06

This bug is part of a group of bugs which have had an open needinfo for at least 12 weeks.

The request for information has not been answered, and we can't move forward on the bug so we are closing it.

If the defect is still present, please reopen this bug with an updated report.