Re: [Libmesh-devel] Memory Leak in DofObject?

[John P. <jwp...@gm...>]

Hi,

I think I may have found the leak...

Check out clear_dofs() in dof_object.h

After deleting _n_v_comp[s], we test to see if there are any dof_ids
to be deleted:

	  if (this->n_vars(s) != 0) // This has only been allocated if
	    {                                  // variables were declared
	      libmesh_assert (_dof_ids[s]  != NULL); delete [] _dof_ids[s];
_dof_ids[s] = NULL;
	    }

However, this->n_vars(s) always returns zero, because we just deleted
_n_v_comp[s].  Therefore, _dof_ids[s] is leaked for each system, at
every destructor call.  I recommend reversing the order of these
delete steps, and we should be good.  I'll test this now and see if it
fixes the leak.

In a more general sense, are we still worried enough about the
overhead of std::vector to warrant all this dynamic memory allocation
business?  I'd like to see some profiling that shows the additional
overhead of std::vector, but on the other hand, I'd rather not rewrite
DofObject first :)

-- 
John