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Heap Dumps                         Interpreting HeapDumps Note:35084.1
~~~~~~~~~~                         Dump subheap by ADDR   Event:HEAPDUMP_ADDR

    You need to make sure that the database has been started with a very large
    MAX_DUMP_FILE_SIZE or trace files may get truncated. Also ensure the
    DUMP_DEST parameters point to where there is LOTS of disk space.


Levels        (use the relevant level in the examples below as <LEVEL>)
~~~~~~
Warning: 'WITH CONTENTS' dumps a hex dump of each chunk of memory in
          the heap.        (not a good idea for the SGA)
  
* 9205 onwards: As 8.0 onwards below but you can add in:
        0x10000000 (268435456)   to also dump the 5 largest subheaps.
        0x20000000 (536870912)   to also dump the 5 largest subheaps
                                 AND the 5 largest within each of those.

        eg: 0x10000001 would dump PGA and its 5 largest subheaps.
            You need the low order bit/s to say what to dump.

* 8.0 onwards: This is a BITWISE flag:                Notification: 8.0 differs from 7.3
        Heap                Level                With Contents
        ~~~~                Hex   Dec         Hex         Dec
        top PGA                0x01    1         0x401         1025
        top SGA                0x02    2         0x802         2050
        top UGA                0x04    4        0x1004         4100
        Current call        0x08    8        0x2008   8200
        User call        0x10   16        0x4010  16400
        Large Pool        0x20   32        0x8020  32800
        Streams Pool    0x40   64      0x10040  65600 * 10g+ only
        Java Pool       0x80  128      0x20080 131200 * 10g+ only

* 7.3 onwards: This is a BITWISE flag:
        Heap                Level                With Contents
        ~~~~                Hex   Dec         Hex         Dec
        top PGA                0x01    1          0x21             33
        top SGA                0x02    2          0x42            66
        top UGA                0x04    4          0x84           132
        Current call        0x08    8         0x108     264
        User call        0x10   16         0x210     528

     To dump sub-heaps in 7.3 first dump the relevant top heap then see
     Event:HEAPDUMP_ADDR       

* Pre 7.3:    (Bits cannot be OR'ed)
        Heap                Level                With Contents
        ~~~~                Hex   Dec             Dec
        top PGA                0x03        3        1000000003
        top SGA                0x01    1        1000000001
        top UGA                0x02        2        1000000002
        top call        0x04    4        1000000004

        OTHER is address of heap to dump


To Dump a Heap:
~~~~~~~~~~~~~~~
*SQL Session:      
    alter session set events 'immediate trace name heapdump level <LEVEL>';

*Dump HEAPDUMP on a given error:
    In init.ora: Eg: event="4031 trace name HEAPDUMP level 2"
    In session: Eg: alter session set events '4031 trace name HEAPDUMP level 2';

*To dump another processes HEAP (UGA etc..):
    Find the process ID / name of the process you need to dump
    (select SPID ,pid,username,program from v$process where ... )

*SQLPLUS (8.0+ generic)
   $ sqlplus /nolog
      connect / as sysdba
      oradebug setospid <process ID>
      oradebug unlimit
      oradebug dump heapdump <LEVEL>

*Server Manager (7.3+ generic)                                Note:29786.1
   $ svrmgrl
      connect internal
      oradebug setospid <process ID>
      oradebug unlimit
      oradebug dump heapdump <LEVEL>

*ORADBX (Unix):                                        Note:28863.1
   $ oradbx
    (oradbx) debug <process ID>
    (oradbx) unlimit trace
    (oradbx) event immediate trace name heapdump level <LEVEL>
    (oradbx) exit


Additional Notes
~~~~~~~~~~~~~~~~
  For memory growth / leak type issues it can be helpful to
  have the instance running with Event:10235 set at level 65536.
  This level causes KGH memory allocations for PERM space to
  include comments against each allocation where possible.
  The comments show as "cprm" chunks under the "perm" chunks
  in the PERMANENT section of the heapdump.

  It can also be helpful, where present, to add 0x20000000 to
  the level so that largest subheaps are also dumped.