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<h2>Cell Type</h2>
<p>The Cell Type view is a low-level view of the layout of the heap. It is
useful for getting a quick feel for fragmentation, for example, but the other
views are more commonly used.</p>
<p><img src="../images/ha_heap_view.png"></p>
<p>The Cell Type view breaks down the heap into word-sized (4 byte) blocks,
each represented by a coloured square. The following colour-coding is applied
to each related group of words for easy identification:</p>
<ul>
<li><strong>White</strong>: Contains a header word, used by the heap
allocator for book-keeping.</li>
<li><strong>Red/Orange</strong>: Contains the data of an allocated object
whose class has been identified via its vtable pointer.</li>
<li><strong>Yellow</strong>: Contains the data of a heap-allocated
descriptor.</li>
<li><strong>Purple/Brown</strong>: Contains the data of an allocated object
whose type cannot be identified, usually a raw data buffer.</li>
<li><strong>Blue</strong>: A free area of the heap that does not currently
contain an allocated object.</li>
</ul>
<p>The colour fade between the start and end of a group of words makes it
easier for you to pick out the beginning and the end of cells.</p>
<p>If you highlight a cell by hovering the mouse over it (the whole of the
associated cell is highlighted), you get a pop-up summary of its contents as a
tool-tip. You can also right-click to bring up a context menu of options.</p>
<p>If you click on a cell to select it, or navigate to it using the cursor keys
or the <strong>Previous / Next</strong> buttons, or search for it by address in
the <strong>Search</strong> box, then that cell will be selected and you will
get a summary in the <strong>Information</strong> box below.</p>
<ul>
<li><strong>Address</strong> is the start of the cell, including book-keeping
info.</li>
<li><strong>Payload</strong> is the address range of the actual data stored
in the cell.</li>
<li><strong>Nesting level</strong> and <strong>Allocation number</strong>
info for a cell are only maintained by the debug (UDEB) version of RHeap,
and rarely used as a result.</li>
</ul>
<p>If you double-click on a cell, a floating memory inspector window will be
displayed, showing you the cell contents. Cells that contain references to
other memory locations are highlighted. Double-clicking a highlighted value
jumps to the referenced location.</p>
<h5>Related references</h5>
<ul>
<li><a href="object_type.htm">Object Type</a></li>
<li><a href="parent_binary.htm">Parent Binary</a></li>
<li><a href="cell_lenght.htm">Cell Lenght</a></li>
<li><a href="isolation.htm">Isolation and Pervasiveness</a></li>
<li><a href="HA_data_analysis.htm">Data analysis with Heap Analyser</a></li>
</ul>
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