Re: importNode() / release() memory growth problem in Xerces-C++.....please help

John Doe wrote:
> Hi, this is the second time I send this message, sorry for that, its just
> that I am not sure it got sent
> the first time, since I didn't receive any responces.
>
> I have the following simple code, using xerces running on my windows.
> This demo compiles and runs normally, but when I open my Task Manager,
> I see a constant memory growth of my process, and I dont understand
> why.
>
> //***********************************************
> XMLPlatformUtils::Initialize();
> DOMImplementation impl =
> DOMImplementationRegistry::getDOMImplementation(...);
> DOMDocument* doc1 = impl->createDocument(...);
> DOMDocument* doc2 = impl->createDocument(...);
> DOMElement* elem1 = doc1->createElement(...);
> DOMElement* elem2 = doc2->createElement(...);
>
> // get elem2 to be realy big element, so that memory leak will be more
> visible
> DOMElement* tmp = doc2->createElement(...);
> for(int i=0; i<50; i++)
> {
>  elem2->appendChild(tmp);
> }
>
> DOMNode* node;
> while(true)
> {
> // thread sleep for 20 msec
> Sleep(20);
> node = doc1->importNode(elem2, true);
> node->release();
> }
>
> //****************************************************
> I understand that importNode() actualy clones the original node, but
> release() is supposed to free it, and it seems that it doesn't happen.
> What is wrong here? please help.

There was a long discussion about this just a few weeks ago:

http://marc.theaimsgroup.com/?l=xerces-c-dev&m=116592343116092&w=2

The bottom line is that you will need to release the parent DOMDocument 
instance to recover all of the memory.

Also, it looks like you're using one DOMDocument instance as a factory, 
creating a large tree, then importing that entire tree into another 
document.  You might want to consider re-factoring your code so you always 
create the new nodes in the document that's the final destination of the 
nodes, since that is much more efficient.

Dave