Using Function Detail Charts to Analyze Memory Usage (Memory Profiling)

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The Function Detail window displays data about a specific method and its immediate callers and descendants. Percentages of allocated memory are displayed using three pie charts.

Note: Pie charts and the method's object list are not shown for diff runs.

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The % of Focus pie chart displays a purple slice to indicate the percentage of memory the selected method and its descendants contributed to the current focus (for example, .Root.). A white slice represents the percentage of memory that all other methods contributed to the current focus. Use this pie chart to assess whether a method contributed a substantial amount of memory to the current focus.

Tip: Methods that contribute small amounts of memory are probably not significant. Look for methods that display large purple slices; they are important contributors to the current focus and can indicate potential memory leaks.

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The Callers pie chart displays color-coded slices to indicate the percentage of the selected method's method + descendants (M+D) bytes that is attributed to each caller. Use this pie chart to walk through the data and follow a method's contribution to the total amount of memory used by the program.

Tip: Double-click large slices to examine a caller's descendants and their memory contributions relative to other callers and descendants.

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The Descendants pie chart displays color-coded slices to indicate the percentage of memory each descendant contributed to the selected method's total M+D bytes. In addition, a light green slice represents the percentage of memory contributed by the selected method itself (as shown in the method data). A gray slice represents the memory contributed by its hidden descendants (also shown in the method data). Use this pie chart to assess a method's memory use, including the memory of hidden methods, relative to its M+D bytes, and relative to each descendant.

Tip: Small slices indicate descendants that contributed little to the selected method's M+D bytes, and are therefore probably not significant. A large slice can indicate a heavy contributor, and it is often worth double-clicking to examine that method's data in detail.

Notes:

§      Only values greater than 1% are displayed in the pie charts.

§      Purify displays up to ten individual methods in the Callers and the Descendants pie charts. Additional methods are grouped together in a white slice labeled Other.

§      Pause the cursor over any pie chart slice to display information about it.

§      Pie charts are not displayed in the diff Function Detail window.

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