[OpenLayers-Users] transitionEffect related performance issue in firefox/ubuntu

[Daniel Behr]

Hello,
maybe this is of interest to someone or someone even knows a workaround. 
Its not primarily an OL issue, but some OL settings have an influence.

Since a while I see extremely bad performance zooming in/out in my OL 
app. panning works fine, but zooming sometimes needs 5 seconds before 
the first new tile shows up (and so on), which makes quick zoom/pan 
actions impossible.

I'm using Ubuntu 10.04 32bit and this happens only in firefox. I'm also 
quite sure that it got worse with every firefox release so that now with 
FF12 it really became annoying.
on the same machine I have a FF 3.6.28, Chrome 18 and SeaMonkey 2.0 
which are much faster (Chrome wins, of course).

I then checked out some colleagues' PCs/Browsers and found out that all 
other combinations (openSUSE,Xubuntu,Windows) are reasonably fast, 
except those also running ubuntu 10.04 32bit with firefox. ubuntu 10.04 
64bit is fast, too.

The main reason is that firefox brings Xorg to 100% CPU usage when 
zooming, which slows down the whole system. that seems to be a well 
known problem, when you google 'ubuntu firefox xorg'. other (ubuntu) 
systems seem to be affected, too.
I tried a few tweaks from the search results but nothing worked for me.

Then I saw that when I switch the baselayer in my app to standard OSM 
everythings works just fine. One of the differences is the 
transitionEffect=resize property on the layer. commenting that makes it 
*alot* faster again.

I really like the transition effect, but I have no clue how many systems 
might be affected and if I should rather not use it.

Are there other OL settings that may trigger browser rendering issues?

thanks
Daniel
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