yes now i can see where you'd want to use dhtml over flash (kidding). How come this info was "bypassed" or "left out" during that argument?
---------------------------------------- From: "Micha Schopman" <[EMAIL PROTECTED]> Sent: Tuesday, March 08, 2005 2:45 AM To: CF-Talk <[email protected]> Subject: OT: Memory Leak in Browsers? Scott, I think there are not many people on this list working extensively with JavaScript in such areas :) I do a lot so you're lucky ;) IE uses a garbage collector, commonly known as mark n sweep. One aspect of these types of garbage collectors is that they don't collect data which has any type of unknown reference to it. Unknown reference? Yes, references between JavaScript objects and DOM objects are unknown to the browser, resulting in circular reference chains. These are the types of references resulting in allocated memory being kept. For performance reasons the DOM nodes are only freed up when closing the browser. Don't be fooled by other browsers, Mozilla/FireFox browsers also leak, in the case of Google Gmaps as twice as bad as IE. To overcome this you have to do memory management yourself. Implementing dispose methods, cleaning up all references by hand, attaching onunload handlers, etc. etc. this requires at least intermediate knowledge of JavaScript. When using ActiveX (MSXML) / XMLHttpRequest you will always suffer from a small memory leak, but that isn't really an issue because the leaks are so small they don't cause any trouble at all. 50MB for an IEXPLORE process is nothing, and if they truly like to invest time and money in such a topic I would definitely define an agreement with them stating that the chances on memory footprint improvement are actually very low and you cannot held responsible for loss of investment. If you'd like more information, contact me of the list, I am using MSN with [EMAIL PROTECTED] This for example leaks 400kb per refresh here, and shows circular reference chains. function Car() { var div = document.createElement('div'); div.appendChild(document.createTextNode('test')); this.el = document.body.appendChild(div); this.el.onmouseover = function() { this.style.backgroundColor = '#f0f0f0'; } this.el.onmouseout = function() { this.style.backgroundColor = 'white'; } } window.onload = function() { for(var i=0; i<200; i++) { new Car(); } } Micha Schopman Project Manager Modern Media, Databankweg 12 M, 3821 AL Amersfoort Tel 033-4535377, Fax 033-4535388 KvK Amersfoort 39081679, Rabo 39.48.05.380 ------------------------------------------------------------------------ ------------------------------------------------------------------------ ----- Modern Media, Making You Interact Smarter. Onze oplossingen verbeteren de interactie met uw doelgroep. Wilt u meer omzet, lagere kosten of een beter service niveau? Voor meer informatie zie www.modernmedia.nl ------------------------------------------------------------------------ ------------------------------------------------------------------------ ----- -----Original Message----- From: Scott Barnes [mailto:[EMAIL PROTECTED] Sent: dinsdag 8 maart 2005 7:45 To: CF-Talk Subject: OT: Memory Leak in Browsers? Basically, most would know about the Internet Explorer Memory leak in terms of Garbage Collection not being able to read our Development minds. My question is, has anyone here actually experienced bad memory leaks? in that have you build an application using massive amounts of DHTML - only 3 months down the track you've had to come back and rebuild stuff simply because it became a memory hog? I ask this as despite the know bug in IE (argueably it could be considered developer bad foreplay but anyway) even if an application after an hours use steals 50mb of RAM (now that would have to be a pretty darn big app mind you) surely that wouldn't affect todays computers? as in most would probably fair to say have around 512mb of Ram at minimum? Also taking into account most Tools can ask upward to 90mb to run anyway (ie java based ones that is). -- Regards, Scott Barnes http://www.mossyblog.com ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Logware (www.logware.us): a new and convenient web-based time tracking application. Start tracking and documenting hours spent on a project or with a client with Logware today. Try it for free with a 15 day trial account. http://www.houseoffusion.com/banners/view.cfm?bannerid=67 Message: http://www.houseoffusion.com/lists.cfm/link=i:4:197780 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
