HP UX Java Software 6 Analyzing Garbage Collection Data, 7 Using the Console, 7 Using the Console, 6 Analyzing Garbage Collection Data

Profiling with -Xeprof......................................................................................................................	61
Profiling with Zero Preparation......................................................................................................	62
Profiling with -agentlib:hprof..........................................................................................................	63
Naming Profile Data Files...............................................................................................................	65
–Xeprof and –agentlib:hprof Profiling Options and Their Corresponding Metrics.............................	65
Approaches to Analyzing Performance Data.......................................................................................	68
Looking at the Data from the Bottom Up........................................................................................	68
Looking at the Data from the Top Down........................................................................................	68
Looking for Inefficiencies in Memory Usage..................................................................................	68
Considerations in Interpreting the Data...............................................................................................	68
Inclusive Versus Exclusive Time.....................................................................................................	69
Time Units.......................................................................................................................................	69
CPU Versus Clock Time.............................................................................................................	69
Locating Summary Information for Saved Data Sets...........................................................................	69
Adjusting Scope....................................................................................................................................	70
Comparing Profiling Data Files ...........................................................................................................	71
Scaling Comparison Data.....................................................................................................................	72
Reading Profiling Histograms..............................................................................................................	73
Key to Thread States Reported by ..................................................................................................	73
Interpreting the Histogram Presentation........................................................................................	74
Using Call Graph Trees.........................................................................................................................	75
Interpreting Call Graph Data..........................................................................................................	75
Example of Node Color Display................................................................................................	76
Options for Manipulating the Call Tree Display.............................................................................	77
Tree Pruning...............................................................................................................................	77
Auto-Expanding the Call Tree...................................................................................................	77
Using Sub-Trees..........................................................................................................................	77
Searching the Trees.....................................................................................................................	78
Using Heuristics to Locate Possible Hot Spots.....................................................................................	78
6 Analyzing Garbage Collection Data .......................................................................	80
Obtaining Garbage Collection Data......................................................................................................	80
Data Collection with -Xverbosegc...................................................................................................	80
Collecting Allocation Site Statistics for Viewing in HPjmeter...................................................	83
Collecting Glance Data for Viewing in HPjmeter......................................................................	83
Collecting GC Data with Zero Preparation.....................................................................................	83
Data Collection with -Xloggc...........................................................................................................	84
Naming GC Data Files.....................................................................................................................	85
-Xverbosegc and -Xloggc Options and Their Corresponding Metrics.................................................	85
Locating Summary Information for Saved Data Sets...........................................................................	86
Comparing Garbage Collection Data Files ..........................................................................................	86
Basic Garbage Collection Concepts......................................................................................................	87
Key to Garbage Collection Types Recognized by HPjmeter...........................................................	87
Understanding the Summary Presentation of GC Data..................................................................	88
Understanding the System Details Captured with GC Data..........................................................	90
7 Using the Console .......................................................................................................	93
Starting the Console..............................................................................................................................	93
Starting the Console On HP-UX......................................................................................................	93
Starting the Console On Linux........................................................................................................	93
Starting the Console On Microsoft Windows..................................................................................	93
Using the Main Window Functions......................................................................................................	93
Data Representation........................................................................................................................	94
Icons and Their Meaning.................................................................................................................	95
Node Agent................................................................................................................................	95
JVM Agent..................................................................................................................................	95

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