Hi, First of all, thanks a lot for your time and help. I forgot to say that the problem is using windows and IE8 (of course…) but I have to support IE for some clients. Also, the class is a test class, is not doing anything “useful”, is just to see how to release the memory in IE, the real application is a huge application with thousands of nodes, variables, events… and after 30 minutes working on IE you have like 500 MB used.
I’ve been making some tests with your code and indeed the memory used is the same doing null to the whole array or just doing delete this.options But the problem is still there, I don’t know how to release the memory used by this.options, using your code, the variable is using almost 450 MB in explorer and this memory is never released. I don’t know how to attach a screenshot here to show you the memory…. So, do you have any idea on how to release the memory? I really need to know how to delete a global variable like this.options and for the moment I don’t see how to it….. Thanks a lot for your time kr, Jose On 22 oct, 14:59, "T.J. Crowder" <[email protected]> wrote: > Hi, > > > I have a big problem in my application, when I create a global class > > object is impossible for me to release the memory and I'm having > > memory leaks. > > It looks to me like you're doing nearly everything you need to do (and > a little bit more). Remember that all you can do is make sure that > memory is no longer referenced (which it looks to me like you've done > almost completely) and that you've broken any _circular_ references > between DOM elements and JavaScript objects (you don't have any > circular references, but you've broken all refs from JavaScript->DOM, > which is a good thing to do). At that point, it's up to the JavaScript > implementation when (and whether) to actually reclaim the memory. Some > are more aggressive than others, and some are more effective than > others. > > Your actual quoted code ends up being very nearly a no-op, which I'm > guessing is for testing purposes. It creates 2,000 divs and pushes > them on an array (and another div it puts in a property) but never > adds them to the document. It then removes the references to them from > the array and releases the array (and clears the property). Assuming > this code: > > var t = new TestClass(); > > ...by the time the line above is complete, the only remaining memory > references I see are the instance itself (`t` above) and the fact that > `t` has a property called `options` (which has the value null). If you > uncomment the `delete this.options;` line, then even the `options` > property that will be gone. > > I took your code and put it (sans alerts) in a page that created 20 > TestClass objects every 250ms and then threw them away. Using Chrome's > excellent about:memory page, I was able to see that the memory does > (eventually) get reclaimed by Chrome, Firefox, and Opera on Linux, IE6 > on Windows 2000, and IE8 on Windows 7. They were wildly different > about when they did it. Chrome started at using 12k for the page, > which shot up to 60k almost immediately (certainly on the first 40-60 > TestClass instances), and then allowed memory use to go up to 85-95k > before reclaiming back down to 62-64k and letting it climb again. > Firefox 3.6 started at about 50k and allowed use to creep up to 250k > before reclaiming back down to ~70k again (rinse, repeat). Opera was > the most aggressive about reclaiming the memory, starting at 38k, > jumping almost immediately to 57k and then staying there, almost > completely steady. On Windows, IE8 started at about 33k and allowed > that to grow to about 57-59k before reclaiming back down to 33k again > and allowing it to grow. (Wow is IE slow.) Even IE6 on Windows 2000 > (measured via Task Manager rather than Chrome) reclaimed the memory > (occillating between 7k and 25k). > > Then I modified the code to retain the TestClass instances, to test > whether the instances were somehow keeping the elements in memory. In > all five cases (Chrome, Firefox, and Opera under Linux, IE8 under > Windows, and IE6 under Windows), they weren't. The memory use was > virtually identical to the first test, which shows that by the time > you've done your "destroy", the instances *don't* retain any memory > references that prevent cleanup. (The instances themselves will be > very small.) > > BTW, you don't need to explicitly null-out the array elements before > releasing the array. I've heard people say you do, but it doesn't make > any sense from a JavaScript specification perspective (not that that > matters, particularly not when you're talking about IE) but this > seemed like a good opportunity to test it for myself. Commenting out > the loop in `destroy` that nulls out the elements made no difference, > not even on IE6. I think it's a myth. > > So that means your `destroy` can consist entirely of this: > > destroy: function() { > delete this.options; > } > > ...since you're keeping everything on the `options` object. > > Here are the test files:http://pastie.org/1240577- the basic counter > testhttp://pastie.org/1240579- keep the instances > testhttp://pastie.org/1240582- don't null out array entries > testhttp://pastie.org/1240613- using the one-liner `destroy` above > > HTH, > -- > T.J. Crowder > Independent Software Engineer > tj / crowder software / com > www / crowder software / com > > On Oct 22, 10:52 am, jose maria Cano <[email protected]> wrote: > > > > > > > > > Hi guys, > > I have a big problem in my application, when I create a global class > > object is impossible for me to release the memory and I'm having > > memory leaks. > > > I've made a small class as example. > > > var TestClass = Class.create({ > > > initialize: function() { > > this.options = { > > vari: '', > > array: '', > > testDiv: '' > > }; > > this.addElement(); > > }, > > addElement: function(element) { > > var a = 0; > > var arrayDivs = []; > > alert('before create element'); > > for (var i = 0; i < 2000; i++) { > > var div = new Element('div'); > > div.innerHTML = 'test' + i; > > arrayDivs.push(div); > > } > > alert('after create element'); > > this.options.vari = 'pepe'; > > this.options.array = arrayDivs; > > this.options.testDiv = new Element('div', { 'id': > > 'testdivPepe' }); > > this.destroy(); > > }, > > destroy: function() { > > alert('before destroy'); > > for (var i = 0; i < this.options.array.length; i++) { > > this.options.array[i] = null; > > //this.options.array.pop(); > > } > > //this.options.array.splice(0, this.options.array.length); > > this.options.testDiv = null; > > this.options.vari = null; > > this.options.array = null; > > this.options = null; > > //delete this.options.array; > > //delete this.options.testDiv; > > //delete this.options.vari; > > //delete this.options; > > alert('after destroy'); > > } > > > }); > > > I've tryed the delete, put the variable to null, to undefined, also > > remove() for the html and no way to release the memory. > > > I really need some help here. can you give a hand here? > > > Kr, Jose -- You received this message because you are subscribed to the Google Groups "Prototype & script.aculo.us" group. 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