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1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> |
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2 <html> |
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3 <head> |
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4 <meta http-equiv="content-type" content="text/html; charset=iso-8859-1"> |
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5 <title>Cell Type</title> |
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6 <link href="../../book.css" type="text/css" rel="stylesheet"> |
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7 </head> |
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8 |
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9 <body> |
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10 <h2>Cell Type</h2> |
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11 |
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12 <p>The Cell Type view is a low-level view of the layout of the heap. It is |
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13 useful for getting a quick feel for fragmentation, for example, but the other |
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14 views are more commonly used.</p> |
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15 |
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16 <p><img src="../images/ha_heap_view.png"></p> |
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17 |
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18 <p>The Cell Type view breaks down the heap into word-sized (4 byte) blocks, |
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19 each represented by a coloured square. The following colour-coding is applied |
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20 to each related group of words for easy identification:</p> |
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21 <ul> |
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22 <li><strong>White</strong>: Contains a header word, used by the heap |
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23 allocator for book-keeping.</li> |
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24 <li><strong>Red/Orange</strong>: Contains the data of an allocated object |
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25 whose class has been identified via its vtable pointer.</li> |
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26 <li><strong>Yellow</strong>: Contains the data of a heap-allocated |
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27 descriptor.</li> |
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28 <li><strong>Purple/Brown</strong>: Contains the data of an allocated object |
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29 whose type cannot be identified, usually a raw data buffer.</li> |
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30 <li><strong>Blue</strong>: A free area of the heap that does not currently |
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31 contain an allocated object.</li> |
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32 </ul> |
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33 |
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34 <p>The colour fade between the start and end of a group of words makes it |
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35 easier for you to pick out the beginning and the end of cells.</p> |
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36 |
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37 <p>If you highlight a cell by hovering the mouse over it (the whole of the |
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38 associated cell is highlighted), you get a pop-up summary of its contents as a |
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39 tool-tip. You can also right-click to bring up a context menu of options.</p> |
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40 |
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41 <p>If you click on a cell to select it, or navigate to it using the cursor keys |
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42 or the <strong>Previous / Next</strong> buttons, or search for it by address in |
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43 the <strong>Search</strong> box, then that cell will be selected and you will |
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44 get a summary in the <strong>Information</strong> box below.</p> |
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45 <ul> |
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46 <li><strong>Address</strong> is the start of the cell, including book-keeping |
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47 info.</li> |
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48 <li><strong>Payload</strong> is the address range of the actual data stored |
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49 in the cell.</li> |
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50 <li><strong>Nesting level</strong> and <strong>Allocation number</strong> |
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51 info for a cell are only maintained by the debug (UDEB) version of RHeap, |
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52 and rarely used as a result.</li> |
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53 </ul> |
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54 |
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55 <p>If you double-click on a cell, a floating memory inspector window will be |
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56 displayed, showing you the cell contents. Cells that contain references to |
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57 other memory locations are highlighted. Double-clicking a highlighted value |
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58 jumps to the referenced location.</p> |
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59 |
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60 <h5>Related references</h5> |
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61 <ul> |
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62 <li><a href="object_type.htm">Object Type</a></li> |
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63 <li><a href="parent_binary.htm">Parent Binary</a></li> |
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64 <li><a href="cell_lenght.htm">Cell Lenght</a></li> |
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65 <li><a href="isolation.htm">Isolation and Pervasiveness</a></li> |
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66 <li><a href="HA_data_analysis.htm">Data analysis with Heap Analyser</a></li> |
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67 </ul> |
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68 |
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69 <div id="footer"> |
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70 Copyright © 2010 Nokia Corporation and/or its subsidiary(-ies). All rights |
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71 reserved. License: <a |
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72 href="http://www.eclipse.org/legal/epl-v10.html">http://www.eclipse.org/legal/epl-v10.html</a>.</div> |
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73 </body> |
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74 </html> |