1Copyright (c) 2003, 2005, Oracle and/or its affiliates. All rights reserved.
2
3Redistribution and use in source and binary forms, with or without
4modification, are permitted provided that the following conditions
5are met:
6
7  - Redistributions of source code must retain the above copyright
8    notice, this list of conditions and the following disclaimer.
9
10  - Redistributions in binary form must reproduce the above copyright
11    notice, this list of conditions and the following disclaimer in the
12    documentation and/or other materials provided with the distribution.
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14  - Neither the name of Oracle nor the names of its
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17
18THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
19IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
20THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
22CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
23EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
24PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
25PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
26LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
27NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
28SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30
31Header for -agentlib:hprof (or -Xrunhprof) ASCII Output (JDK 5.0 JVMTI based)
32
33WARNING!  This file format is under development, and is subject to
34change without notice.
35
36This file contains the following types of records:
37
38THREAD START
39THREAD END      mark the lifetime of Java threads
40
41TRACE           represents a Java stack trace.  Each trace consists
42                of a series of stack frames.  Other records refer to
43                TRACEs to identify (1) where object allocations have
44                taken place, (2) the frames in which GC roots were
45                found, and (3) frequently executed methods.
46
47HEAP DUMP       is a complete snapshot of all live objects in the Java
48                heap.  Following distinctions are made:
49
50                ROOT    root set as determined by GC
51                CLS     classes
52                OBJ     instances
53                ARR     arrays
54
55SITES           is a sorted list of allocation sites.  This identifies
56                the most heavily allocated object types, and the TRACE
57                at which those allocations occurred.
58
59CPU SAMPLES     is a statistical profile of program execution.  The VM
60                periodically samples all running threads, and assigns
61                a quantum to active TRACEs in those threads.  Entries
62                in this record are TRACEs ranked by the percentage of
63                total quanta they consumed; top-ranked TRACEs are
64                typically hot spots in the program.
65
66CPU TIME        is a profile of program execution obtained by measuring
67                the time spent in individual methods (excluding the time
68                spent in callees), as well as by counting the number of
69                times each method is called. Entries in this record are
70                TRACEs ranked by the percentage of total CPU time. The
71                "count" field indicates the number of times each TRACE
72                is invoked.
73
74MONITOR TIME    is a profile of monitor contention obtained by measuring
75                the time spent by a thread waiting to enter a monitor.
76                Entries in this record are TRACEs ranked by the percentage
77                of total monitor contention time and a brief description
78                of the monitor.  The "count" field indicates the number of
79                times the monitor was contended at that TRACE.
80
81MONITOR DUMP    is a complete snapshot of all the monitors and threads in
82                the System.
83
84HEAP DUMP, SITES, CPU SAMPLES|TIME and MONITOR DUMP|TIME records are generated
85at program exit.  They can also be obtained during program execution by typing
86Ctrl-\ (on Solaris) or by typing Ctrl-Break (on Win32).
87