We present a visualization tool/or dynamic memory allocation information obtained from instrumenting the runtime allocator used by C programs. The goal of the presented visualization techniques is to convey insight in the dynamic behavior of the allocator. The purpose is to help the allocator designers understand how the performance and working of the allocator depend on the actual allocation scenarios in order to optimize its functionality by decreasing fragmentation and improving response lime. We use an orthogonal dense pixel layout of time versus memory space which can show tens of thousands of allocation events on a single screen. We enhance the basic idea with several new techniques: antialiased metric bars for detecting high and low activity areas; cushion cursors for checking correlations of multiple views; and a view to show correlation between program structure (functions) and memory allocations. The presented techniques are demonstrated on data from a real application.