|
Problem IC64116
|
Status: Closed |
INSTANCE CRASH DUE TO STACK OVERFLOW WITH FUNCTION SQLNG_PROCESS_BF_NODE OR SQLNG_PROCESS_PARSE_TREE_NODE |
| product: |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 |
| Problem description: |
During SQL compilation, a query being compiled may cause the DB2
instance to crash due to a stack overflow exception. However,
the new behaviour in DB2 Version 9.5 should ideally cause the
DB2 agent to return an sqlcode SQL0973N upon detecting such a
scenario.
The stack trace from such an abend will look like:
-------Frame------ ------Function + Offset------
0x0900000004C8FC94
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x50
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
*
* The function sqlng_process_parse_tree_node() and
sqlng_process_BF_node is repeated many times
*
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
.... |
| Problem Summary: |
Users Affected:
The users who are running a very complex query that requires
excessive amount of stack space to be compiled.
PROLBEM:
During SQL compilation, a query being compiled may cause the DB2
instance to crash due to a stack overflow exception. However,
the new behaviour in DB2 Version 9.5 and later should ideally
cause the DB2 agent to return an sqlcode SQL0973N upon detecting
such a scenario.
The stack trace from such an abend will look like:
-------Frame------ ------Function + Offset------
0x0900000004C8FC94
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x50
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
*
* The function sqlng_process_parse_tree_node() and
sqlng_process_BF_node is repeated many times
*
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
0x0900000004C9108C
sqlng_process_parse_tree_node__FP9sqlng_blkP9sqlnq_pid + 0x1448
0x0900000005AF8DB0
sqlng_process_BF_node__FP9sqlng_blkP9sqlnq_pid + 0x134
.... |
| Local Fix: |
In DB2 Version 9.5, users have the ability to control the size
of the runtime stack used by a DB2 agent.
Consequently,increasing the value for the "agent_stack_sz"
database configuration parameter will help workaround the
issue. |
| Solution |
Problem was fixed in Version 9.7 Fix Pack 1 |
| Workaround |
In DB2 Version 9.5 and later, users have the ability to control
the size of the runtime stack used by a DB2 agent.
Consequently,increasing the value for the "agent_stack_sz"
database configuration parameter will help workaround the issue. |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 23.10.2009
19.11.2009
19.11.2009 |
| Problem solved at the following versions (IBM BugInfos) |
9.7.FP1
|
| Problem solved according to the fixlist(s) of the following version(s) |
