IE8 - dismally slow

I just installed IE8 and find that my dhtmlx apps run so slowly as to be useless. I managed to run the profiler once and it reported that almost all the time was spent in the dhtmlx function setsizes (this was true for IE7 as well but it was just unacceptably slow rather than dismally slow)

I can’t see a way to attach my sample here but I sent it to you last night as part of a support request. Subject Line was “Bob Palin - support request” with two files attached.

I ran one of your samples and that seemed to be OK so I’d like to know what the secret is?

The existing version has known issue with IE8b2 and IE8RC1 when page loaded in IE8 standard mode - issue already fixed in dev. build and will be released as part of oncoming updated.
For now you can load page in “compatibility” or “quirks” mode - they must work correctly, or contact us at to receive some kind of hotfix.

I only loaded IE8 because performance in IE7 was so bad and IE8 was supposed to be better for JS execution & DOM management.  In the example I sent you (and attached here again) it takes 5-7 seconds for the tabs to switch when clicked on - no user code is running at all, just dhtmlx. In Firefox this switch takes about 1 second but I can’t require my clients to use just Firefox. (961 Bytes)
tabmenutest.htm (9.11 KB)

Situation confirmed, with provided test page performance in IE is really bad. We will investigate possible reasons. Meanwhile some recommendation for improving performance of provided layouts sent by email.