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[QA-28] ORA-00600 [729]: UGA memory leak. Created: 15/Jul/07  Updated: 16/Sep/07

Status: Closed
Project: Questions & Answers
Fix Version/s: None

Type: Oracle - Internals Priority: Major
Reporter: ubTools Support Assignee: ubTools Support
Resolution: Answered Votes: 0

Product Version: 8.1.7.3.0
Operating System: Windows
Operating System Version: 2000

 Description   
ORA-00600 [729]: UGA memory leak.

 Comments   
Comment by ubTools Support [ 15/Jul/07 06:04 PM ]

Error code:

ORA-00600: internal error code, arguments: [729], [480], [space leak], [], [], [], [], []

Error code definition:

A space leak has been detected in the User Global Area (UGA). There is no data corruption as a result of this error. It is an internal memory housekeeping problem. Second argument is the number of bytes leaked.

UGA Heap dump:

******** ERROR: UGA memory leak detected 480 ********
******************************************************
HEAP DUMP heap name="session heap"  desc=0x222bd6f4
extent sz=0x108c alt=32767 het=32767 rec=0 flg=3 opc=3
parent=212550 owner=ad83d50 nex=0 xsz=0x108c
EXTENT 0
 Chunk 2330b100 sz=     3844    free      "               "
EXTENT 1
 Chunk 232f5174 sz=      516    free      "               "
EXTENT 2
 Chunk 236f0050 sz=     4176    free      "               "
EXTENT 3
 Chunk 236d0050 sz=     1228    free      "               "
EXTENT 4
 Chunk 236f18e4 sz=     1280    free      "               "
EXTENT 5
 Chunk 23307098 sz=     4228    free      "               "
EXTENT 6
 Chunk 2330a27c sz=     3696    free      "               "
EXTENT 7
 Chunk 23308130 sz=     1008    free      "               "
 Chunk 23308520 sz=      480    freeable  "define var info"
 Chunk 23308700 sz=     2740    free      "               "
EXTENT 8
 Chunk 23306214 sz=     2832    perm      "perm           "  alo=2832
 Chunk 23306d24 sz=      864    free      "               "
EXTENT 9
 Chunk 233091c8 sz=     4228    free      "               "
EXTENT 10
 Chunk 232f405c sz=      612    free      "               "
EXTENT 11
...

Problem explanation:

As seen in the UGA heap dump, there is a freeable chunk of define var info memory type. This chunk looks leaked.

Workaround:

There is no data corruption in this error, and can be safely ignore for small memory leaks by adding the following event to init.ora:

  • event = "10262 trace name context forever, level 500"

Then, restart your database. This event disables space leaks less than 500 bytes.

You can see the details at Metalink Note:31056.1 ORA-600 [729] "UGA Space Leak"

Bug:

Bug:2177050: ORA-600 [729] after application of the 8.1.7.3 patchset. The resulting trace file will include a memory dump which shows unfreed memory chunks with the tags "define var info" and/or "oactoid info".
Ref: Metalink Note:31056.1 ORA-600 [729] "UGA Space Leak"

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