Javascript scrolling gig list causes high CPU on Firefox 3.6

[Mark Davies]

I have just noticed that the Javascript scrolling gig list causes high CPU on my system on the latest Firefox 3.6.3 (on Windows XP SP3).

With only Firefox running, and with one tab open at the Manband Forum, Firefox uses about 25% CPU on my dual processor system (i.e. about half a processor). If I open up a second tab with the Manband Forum, it maxes out at 50% CPU (i.e. 100% of a processor).

I can reproduce this behaviour on another system. Also, IE & Chrome do not exhibit the problem.

If I disable Javascript, then the CPU problem goes away. In fact, if I hover over the scrolling gig list with my mouse cursor, then the gig list stops scrolling and the Firefox CPU usage drops to zero (ish).

Looking at the Javascript, it uses "Cross browser Marquee II" for the scrolling gig list. Googling shows that this is a known problem (which has actually been around for at least a year), with a suggested fix to initializemarquee():

http://www.dynamicdrive.com/forums/archive/index.php/t-41987.html

[Jules]

I've applied that patch, with some tweaks to make it work inside the <div> boundaries rather than scroll the entire page (ouch!). CPU usage is still pretty high on IE when scrolling (drops when paused). CPU seems better on Firefox, Safari, Chrome and Opera.

Let me know how it's working for you know?

[Mike Morgan]

I was with you as far as 'good morning'.  Hope whatever needs to to get sorted does.

Staying up for the election results and losing the plot by the minute!

[Mark Davies]

I've applied that patch, with some tweaks to make it work inside the <div> boundaries rather than scroll the entire page (ouch!). CPU usage is still pretty high on IE when scrolling (drops when paused). CPU seems better on Firefox, Safari, Chrome and Opera.

Let me know how it's working for you know?

Sorry, but to me, it appears no better, and possibly worse.

[Jules]

Interesting. I certainly saw a small improvement, maybe a 15% drop or thereabouts (not on IE though).

I shall mull.......

[Rob W]

I was with you as far as 'good morning'.  Hope whatever needs to to get sorted does.

Well I thought them two were talking a right load of b*ll*cks. But then I noticed, neither said "good morning", so what are you goin' on about?

[Mike Morgan]

Quote from Red Dwarf.  Lister listened to a lenghty explanation about something techy from Kryten and at the end said  I was with you...

Another one:

Cat: I'm so hungry. I just have to eat!
Lister: Shh... Rimmer's dad's died.
Cat: I'd prefer chicken.

[Jules]

I've now swapped out the marquee2 script for another with similar functionality. This looks a little clunkier in IE, but is less cpu hungry.

Checked on IE8, Firefox 3.6.3, Opera 9.8, Safari 4.5.5  and Chrome 4.1.249.1064.

[Rob W]

I've now swapped out the marquee2 script for another with similar functionality. This looks a little clunkier in IE, but is less cpu hungry.

Checked on IE8, Firefox 3.6.3, Opera 9.8, Safari 4.5.5  and Chrome 4.1.249.1064.

Thank f*ck for that


 

[Mike Morgan]

I've now swapped out the marquee2 script for another with similar functionality. This looks a little clunkier in IE, but is less cpu hungry.

Checked on IE8, Firefox 3.6.3, Opera 9.8, Safari 4.5.5  and Chrome 4.1.249.1064.

I was just about to post that as an option you might have wished to consider

[Nick Nation]

I've now swapped out the marquee2 script for another with similar functionality. This looks a little clunkier in IE, but is less cpu hungry.

Yeah, but now my video doesn't rewind.

[Jules]

Yeah, but now my video doesn't rewind.

Turn your screen round and run it backwards.

[Nick Nation]

...but at least I've got the hang of using the 'quote' box....

[Jules]

 

[Mark Davies]

I've now swapped out the marquee2 script for another with similar functionality. This looks a little clunkier in IE, but is less cpu hungry.

Checked on IE8, Firefox 3.6.3, Opera 9.8, Safari 4.5.5  and Chrome 4.1.249.1064.

Looks good to me. Thanks. Glad to see the ManBoard is maintaining its eco-friendly, green credentials