Want to win a PS4? Go Premium and enter to win our High-Tech Treats giveaway. Enter to Win


IE javascript memory usage

Posted on 2008-10-08
Medium Priority
Last Modified: 2013-12-08
Load a page with the below code in IE7, the memory usage of the browser shoots up to about 100megs on my system and doesn't reduce down until the page is unloaded.  How do I clean up the memory the unused object is taking up?

In firefox if you try this the memory usage spikes and then a few seconds later reduces down, looks like their garbage collector takes care of it.
<script type="text/javascript">
    var obj = [];
    for (var x = 0; x < 999999; x++) obj[obj.length] = "a";
    obj = null;
    delete obj;

Open in new window

Question by:eChalk
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 3
LVL 44

Expert Comment

ID: 22674617
is there a purpose to this 1 million iteration loop?  Or are you just testing to see if javascript can tie up the entire system resources via the browser -- the answer is YES IT CAN !!

Author Comment

ID: 22674978
I have an extremely large page with lots of javascript objects and 3rd party components, and every time i refresh it is not releasing all of it's memory and growing very large in memory usage until the browser is closed.  This is a first step for me to be able to clean up... I'm wondering if in this case there is any way to clear the object from the browser memory without unloading the page.
LVL 18

Accepted Solution

Hube02 earned 1500 total points
ID: 22675017
IE is known to have memory leaks, however, other browsers will also leak memory to some extent. There are many things that can cause this memory leakage and perhaps the code on your page incorporates some of the know issues.

You could start here: http://www.codeproject.com/KB/scripting/leakpatterns.aspx

Although, if you are using 3rd party components the problems may be difficult to locate. Many developers do not keep the problems in mind and in some cases do not know they are creating a problem. And then again, in some cases, it is not possible to avoid the problem completely.
Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

LVL 44

Expert Comment

ID: 22675051
"I have an extremely large page with lots of javascript objects and 3rd party components"

OK, the way to debug this is to run firefox, and use tools, error console, and look for any errors.  There are also more elaborate tools like firebug -- www.getfirebug.com/ -- which will tell you where the problems are.  

It would be a first guess to check the 3rd party components, that is what most would say.  But in your case if you are using javascript objects, I think that is the most likely place to look -- these objects will not be being closed correctly, and accumulate in the hundreds or thousands.  Try the debugging tools in firefox.

Author Comment

ID: 22678453
Firefox does not have as bad a leak as IE.  What tools are available in firefox to spot leaks?  I know of this one for IE (best of the ones i looked at): http://blogs.msdn.com/gpde/pages/javascript-memory-leak-detector.aspx
LVL 44

Expert Comment

ID: 22680912
In FF, there is the built-in error console -- for more elaborate checking of objects not being closed, try their Firebug Plug in --  https://addons.mozilla.org/firefox/addon/1843
LVL 44

Expert Comment

ID: 22852162
how come the comment 22680912 was not accepted then?

Author Comment

ID: 22852217
Because Firebug doesn't have an in depth memory tracing module.  Once the page unloads, theres no window to go to to see all the stuff still hanging, like the JavaScript Memory Leak Detector for IE.

Featured Post

Concerto Cloud for Software Providers & ISVs

Can Concerto Cloud Services help you focus on evolving your application offerings, while delivering the best cloud experience to your customers? From DevOps to revenue models and customer support, the answer is yes!

Learn how Concerto can help you.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Nothing in an HTTP request can be trusted, including HTTP headers and form data.  A form token is a tool that can be used to guard against request forgeries (CSRF).  This article shows an improved approach to form tokens, making it more difficult to…
Originally, this post was published on Monitis Blog, you can check it here . In business circles, we sometimes hear that today is the “age of the customer.” And so it is. Thanks to the enormous advances over the past few years in consumer techno…
The viewer will learn the basics of jQuery including how to code hide show and toggles. Reference your jQuery libraries: (CODE) Include your new external js/jQuery file: (CODE) Write your first lines of code to setup your site for jQuery…
Google currently has a new report that is in beta and coming soon to Webmaster Tool accounts. This Micro Tutorial will highlight new features for Google Webmaster Tools.

610 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question