|
Problem IC72564
|
Status: Closed |
MEMORY LEAK WHEN RUNNING CLI/ODBC APPLICATION THAT ALLOCATES AND FREES AN ENVIRONMENT HANDLE FOR EVERY ITERATION IN THE PROCESS. |
| product: |
DB2 CONNECT / DB2CONNCT / 950 - DB2 |
| Problem description: |
A CLI / ODBC application can have a memory leak if the
application makes the following series of calls in a loop:
SQLAllocHandle (SQL_HANDLE_ENV)
SQLAllocHandle (SQL_HANDLE_DBC)
SQLConnect()
SQLDisconnect()
SQLFreeHandle (SQL_HANDLE_DBC)
SQLFreeHandle (SQL_HANDLE_ENV)
This can also occur if the application process spawns threads
that perform those sequence of calls and multiple threads are
invoked.
This memory leak will only occur when the db2app.dll library is
being unloaded and reloaded. When using the DB2 CLI/ODBC driver
with Microsoft's ODBC driver manager, the memory leak will occur
since the ODBC driver unloads db2app.dll when SQLFreeHandle
(SQL_HANDLE_ENV) is called. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* Windows *
****************************************************************
* PROBLEM DESCRIPTION: *
* A CLI / ODBC application can have a memory leak if the *
* application makes the following series of calls in a loop: *
* *
* SQLAllocHandle (SQL_HANDLE_ENV) *
* SQLAllocHandle (SQL_HANDLE_DBC) *
* SQLConnect() *
* SQLDisconnect() *
* SQLFreeHandle (SQL_HANDLE_DBC) *
* SQLFreeHandle (SQL_HANDLE_ENV) *
* *
* *
* This can also occur if the application process spawns *
* threads that perform those sequence of calls and multiple *
* threads are invoked. *
* *
* This memory leak will only occur when the db2app.dll library *
* is being unloaded and reloaded. When using the DB2 CLI/ODBC *
* driver with Microsoft's ODBC driver manager, the memory leak *
* will occur since the ODBC driver unloads db2app.dll when *
* SQLFreeHandle (SQL_HANDLE_ENV) is called. *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 Version 9.5 Fixpack 8 *
**************************************************************** |
| Local Fix: |
Instead of allocating a new environment handle for each
iteration, just use one environment handle. Then allocate a new
connection handle for each iteration from that environment
handle. If using threads, allocate the environment handle in
the main thread, and allocate the connection handles in the
child thread. |
| available fix packs: |
DB2 Version 9.5 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
First fixed in DB2 UDB Version 9.5, Fixpack 8 |
| Workaround |
see Local Fix |
| BUG-Tracking |
forerunner : APAR is sysrouted TO one or more of the following: IC72649 IC72650
follow-up : |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 12.11.2010
07.07.2011
07.07.2011 |
| Problem solved at the following versions (IBM BugInfos) |
9.5.FP8
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.5.0.8
|
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