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5 <title>Isolation and Pervasiveness</title> |
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10 <h2>Isolation and Pervasiveness</h2> |
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11 |
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12 <p>The Isolation and Pervasiveness views are about highlighting reference |
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13 density.</p> |
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14 |
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15 <p>The <strong>Isolation</strong> view shades objects from cold (blue) to hot |
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16 (more red) based on how “popular” they are with other objects. The |
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17 actual incoming reference count is also displayed in the box at the start of |
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18 each object. Darkest blue objects with a red zero count indicate objects that |
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19 have no references at all within the heap itself. That does not necessarily |
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20 mean they are orphans that have been leaked; they could be referenced from the |
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21 stack or from static variables instead. However, if you do think you may have a |
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22 memory leak then these zero count objects are a good place to start looking.</p> |
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23 |
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24 <p><img src="../images/ha_heap_view_isolation.png"></p> |
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25 |
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26 <p>The <strong>Pervasiveness</strong> view is the inverse of the Isolation |
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27 view. In Pervasiveness view, objects are shaded from cold (blue) to hot (more |
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28 red) based on how many other objects they are “interested” in. The |
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29 actual outgoing reference count is also displayed in the box at the start of |
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30 the object. The other highlighted boxes within cells are the actual locations |
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31 of the potential outgoing references Heap Analyser has identified. As pure data |
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32 datatypes with no outgoing references, descriptors are distinguished in yellow |
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33 here. If you have a memory leak, bright red objects may be worth investigating |
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34 as the potential home to an abnormally large number of references. For example, |
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35 the buffer object within a large array of pointers may be highlighted in this |
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36 view, and in some cases could be the source of a leak e.g. due to forgetting to |
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37 delete objects from the array when they’re no longer needed.</p> |
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38 |
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39 <p><img src="../images/ha_heap_view_pervasiveness.png"></p> |
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40 |
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41 <h5>Related references</h5> |
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42 <ul> |
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43 <li><a href="cell_type.htm">Cell Type</a></li> |
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44 <li><a href="object_type.htm">Object Type</a></li> |
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45 <li><a href="parent_binary.htm">Parent Binary</a></li> |
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46 <li><a href="cell_lenght.htm">Cell Lenght</a></li> |
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47 <li><a href="HA_data_analysis.htm">Data analysis with Heap Analyser</a></li> |
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48 </ul> |
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49 |
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