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<h2>Isolation and Pervasiveness</h2>
<p>The Isolation and Pervasiveness views are about highlighting reference
density.</p>
<p>The <strong>Isolation</strong> view shades objects from cold (blue) to hot
(more red) based on how “popular” they are with other objects. The
actual incoming reference count is also displayed in the box at the start of
each object. Darkest blue objects with a red zero count indicate objects that
have no references at all within the heap itself. That does not necessarily
mean they are orphans that have been leaked; they could be referenced from the
stack or from static variables instead. However, if you do think you may have a
memory leak then these zero count objects are a good place to start looking.</p>
<p><img src="../images/ha_heap_view_isolation.png"></p>
<p>The <strong>Pervasiveness</strong> view is the inverse of the Isolation
view. In Pervasiveness view, objects are shaded from cold (blue) to hot (more
red) based on how many other objects they are “interested” in. The
actual outgoing reference count is also displayed in the box at the start of
the object. The other highlighted boxes within cells are the actual locations
of the potential outgoing references Heap Analyser has identified. As pure data
datatypes with no outgoing references, descriptors are distinguished in yellow
here. If you have a memory leak, bright red objects may be worth investigating
as the potential home to an abnormally large number of references. For example,
the buffer object within a large array of pointers may be highlighted in this
view, and in some cases could be the source of a leak e.g. due to forgetting to
delete objects from the array when they’re no longer needed.</p>
<p><img src="../images/ha_heap_view_pervasiveness.png"></p>
<h5>Related references</h5>
<ul>
<li><a href="cell_type.htm">Cell Type</a></li>
<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="HA_data_analysis.htm">Data analysis with Heap Analyser</a></li>
</ul>
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