Huge memory leak when restarting Irrlicht...

[robmar]

Sounds good, whats the function call to get the total count?

[CuteAlien]

We're talking about maybe adding a feature, so obviously there can't be a function call yet.

[robmar]

So I could just add a global counter and increment it in the grab function..

[serengeor]

So I could just add a global counter and increment it in the grab function..

yeah, that's the idea

[robmar]

Okay, here are the details of my code in which I seem to have a memory leak somewhere.

From the head file for getMesh, it says not to drop the returned mesh pointer:-

virtual IAnimatedMesh* getMesh(const io::path& filename) = 0;
....
//! Get pointer to an animateable mesh. Loads the file if not loaded already. * \return Null if failed, otherwise pointer to the mesh.
* This pointer should not be dropped. See IReferenceCounted::drop() for more information.
**/
virtual IAnimatedMesh* getMesh(const io::path& filename) = 0;

So I don´t drop it, but before reloading a new scene from a file, I remove the meshes. Strangely, aftercalling getMeshCount and removing that number of meshes, when calling getMeshCoutn again, there are still meshes to delete!!! So I have to run the remove loop again! Is there an explication for this behaviour?

cpp Code: Select all

 
        // Ensure all 3D resources freed
        if ( m_pDriver )
        {
                // Delete all meshes
                if ( m_pSmgr )
                {
                        IAnimatedMesh *pMesh;
                        int i, iMl = 0;
                        IMeshCache* pMeshCache = m_pSmgr->getMeshCache();
                        if ( pMeshCache )
                        {
dml:            s32 iMeshCount = pMeshCache->getMeshCount();
                                for ( i = 0; i < iMeshCount; i++ )
                                {
                                        pMesh = pMeshCache->getMeshByIndex( i );
                                        if ( pMesh )
                                                pMeshCache->removeMesh( pMesh );
                                }
 
                                if ( iMl < 10 && pMeshCache->getMeshCount() )
                                {
                                        iMl++;
                                        goto dml;
                                }
                        }
                        else
                        {
                                ASSERT( false );
                                return -1;
                        }
                        m_pMeshCube = NULL;                             // Has now been deleted
                }
 
 

[CuteAlien]

Problem is this line:

cpp Code: Select all

 
pMesh = pMeshCache->getMeshByIndex( i );
 

If you remove the first element - the next element has now index 0.
So what you should use here is not i but 0, then all elements will be removed. If you start removing from the back it will be even faster - and then you can use an index (just be careful not to use an unsigned index and check for >= 0 ).

[robmar]

Oh no.... not again, I made that mistake last week too!!

So thanks, um, just popping out to jet wash my neurons!!

This is the new code, removing from back to avoid causing the internal copy-down:

cpp Code: Select all

 
        u32 uMeshCount = pMeshCache->getMeshCount();
                        for ( u32 ui = uMeshCount; ui > 0; ui-- )
                        {
                                pMesh = pMeshCache->getMeshByIndex( ui-1 );
                                if ( pMesh )
                                        pMeshCache->removeMesh( pMesh );
                        }
 

[hendu]

Just curious, why not use ->clear()?

[robmar]

Good question... if a mesh has more than one grab on it, clear won´t delete it, and then it won´t clear up the array allocations. So I am trying to do this in a controlled way, and handle multiple grabs.

[serengeor]

You shouldn't have it grabbed multiple times in the first place before clearing, cause if it is grabbed by some class, that class expects it to still be available until it drops it.

[robmar]

Yes of course, but the thing is to know this has happened so the code can be fixed, which clear doesn´t report.

[hendu]

clear()
getMeshCount()
?

[robmar]

yes, that works! I was just testing

[robmar]

I´ve also found a massive memory leak with the opengl driver even on the beta 1.8.0 driver, around 12+ MB on closing, which does not occur when using the D3D driver.

Win 7 32-bit, Irrlicht 1.7.2. through to 1.8.0 SVB 4309

[hendu]

1.8 final is out