I can confirm that IE8 is far and away better than IE6 and IE7, and is actually quicker than FF3 in our Qooxdoo app. We're using 0.7.4. If it's at all possible to upgrade to IE8, I strongly recommend that you do so. :)
IE6 and IE7 have memory leaks caused by circular references between JS objects and DOM objects, because they are tracked by different "garbage collectors" (I use that term loosely). IE8 still has some memory leaks, most visible for long-running applications. I found this page just this morning while investigating memory leaks in our application: http://www.outofhanwell.com/ieleak/index.php?title=Fixing_Leaks The most interesting tidbit on that page is the section titled "Pseudo-Leaks". <quote> Sometimes Internet Explorer keeps items in memory after the page is done using them. Although these pseudo-leaks are freed after the user leaves the page, some web pages may be open for long periods of time. To avoid pseudo-leaks, do not use removeChild to remove elements. Instead, set the parent's innerHTML to "" or use a function like this: function discardElement(element) { var garbageBin = document.getElementById('IELeakGarbageBin'); if (!garbageBin) { garbageBin = document.createElement('DIV'); garbageBin.id = 'IELeakGarbageBin'; garbageBin.style.display = 'none'; document.body.appendChild(garbageBin); } // move the element to the garbage bin garbageBin.appendChild(element); garbageBin.innerHTML = ''; } </quote> Adapting the above technique, I got rid of a 3Mb memory leak from our use of qx.ui.embed.HtmlEmbed. I suspect that the virtual table cells created for qx.ui.table.Table also suffer from this pseudo-leak, but I haven't fully investigated yet. This technique is probably something that can be adapted to the qooxdoo framework by placing code in the destructor of qx.ui.core.Widget. (Disclaimer, only using Qooxdoo 0.7.4, not sure which classes have changed in 0.8.X) Bryan -----Original Message----- From: Jim Hunter [mailto:[email protected]] Sent: Monday, April 20, 2009 11:46 AM To: qooxdoo Development Subject: Re: [qooxdoo-devel] Internet Explorer performance I can confirm that the JavaScript engine in IE is horribly slow compared to any other browser. Reusing objects helps dramatically because IE is also horrible at freeing memory. Even if you clear all your objects out, IE may never release them. It is so bad, that not even closing the page and reopening it helps. I have found the memory usage to be so bad that the only way to reclaim it is to close the browser and start over. And this has nothing to to with qooxdoo, it is entirely an IE bug that can not be overcome with code. I have not done drastic testing with IE8, I hope it is better then 6 & 7. Jim On Mon, Apr 20, 2009 at 6:37 AM, Stefan Volbers <[email protected]> wrote: > > > Fabian Jakobs wrote: > >> IE really is so slow but there are a few things you can do: > >> 2. Use the build version. Some of the optimizations are especially >> useful for IE > > Hi Massimo, > see here: > > http://qooxdoo.org/documentation/0.8/snippets?s=mshtml > > for browser specific optimization (but bear in mind that it might break > the app for other browsers). > I cannot confirm your bad results with IE. Have had bad experiences in > the past, too, but qooxdoo 0.8(.2) was a great improvement. BTW, which > version are you using? > > Greetings, > Stefan > > > ------------------------------------------------------------------------------ > Stay on top of everything new and different, both inside and > around Java (TM) technology - register by April 22, and save > $200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco. > 300 plus technical and hands-on sessions. Register today. > Use priority code J9JMT32. http://p.sf.net/sfu/p > _______________________________________________ > qooxdoo-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/qooxdoo-devel > ------------------------------------------------------------------------------ Stay on top of everything new and different, both inside and around Java (TM) technology - register by April 22, and save $200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco. 300 plus technical and hands-on sessions. Register today. Use priority code J9JMT32. http://p.sf.net/sfu/p _______________________________________________ qooxdoo-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/qooxdoo-devel ------------------------------------------------------------------------------ Stay on top of everything new and different, both inside and around Java (TM) technology - register by April 22, and save $200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco. 300 plus technical and hands-on sessions. Register today. Use priority code J9JMT32. http://p.sf.net/sfu/p _______________________________________________ qooxdoo-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/qooxdoo-devel
