|
Problem IC77950
|
Status: Closed |
CLI ASYNCHRONOUS EXECUTION MAY CAUSE POOR PERFORMANCE DUE TO 1 SEC DELAY. |
| product: |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 |
| Problem description: |
A CLI based application might intermittently run slow if the
application enables asynchronous execution. CLI applications can
enable asynchronous execution by the code like as below:
RC = SQLSetStmtAttr( hstmt,
SQL_ATTR_ASYNC_ENABLE,
(SQLPOINTER) SQL_ASYNC_ENABLE_ON,
0);
The db2trc shows the following 1 sec delay on the application
thread when the application runs into this performance problem.
40095 1.735732055 SQLExecute entry
40130 1.735823966 | CLI_asyncRequest entry
40133 1.735830950 | | sqloAppWaitOnSync entry
40136 2.730424676 | | sqloAppWaitOnSync data [probe 20:
WAIT_TIMEOUT]
40137 2.730431102 | | sqloAppWaitOnSync exit |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* Users who use CLI interface with asynchronous execution. *
****************************************************************
* PROBLEM DESCRIPTION: *
* A CLI based application might intermittently run slow if the *
* application enables asynchronous execution. *
* *
* The db2trc shows the following 1 sec delay on the *
* application *
* thread when the application runs into this performance *
* problem. *
* *
* 40095 1.735732055 SQLExecute entry *
* 40130 1.735823966 | CLI_asyncRequest entry *
* 40133 1.735830950 | | sqloAppWaitOnSync entry *
* 40136 2.730424676 | | sqloAppWaitOnSync data [probe 20: *
* WAIT_TIMEOUT] *
* 40137 2.730431102 | | sqloAppWaitOnSync exit *
****************************************************************
* RECOMMENDATION: *
* Please upgrade to V9.7 FixPack 6 or later, then set *
* patch2=112 in db2cli.ini. *
**************************************************************** |
| Local Fix: |
Users can bypass this issue by disabling asynchronous execution.
Please implement one of the followings:
a) Turn SQL_ATTR_ASYNC_ENABLE off in the application code.
b) Set ASYNCENABLE=0 in db2cli.ini
c) Set DisableAsyncQueryExecution as 1 in db2dsdriver.cfg. |
| available fix packs: |
DB2 Version 9.7 Fix Pack 6 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 7 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9a for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
This problem is first fixed in DB2 V9.7 FixPack 6. |
| Workaround |
Users can bypass this issue by disabling asynchronous execution.
Please implement one of the followings:
a) Turn SQL_ATTR_ASYNC_ENABLE off in the application code.
b) Set ASYNCENABLE=0 in db2cli.ini
c) Set DisableAsyncQueryExecution as 1 in db2dsdriver.cfg. |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 05.08.2011
12.06.2012
12.06.2012 |
| Problem solved at the following versions (IBM BugInfos) |
9.7.FP6
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.7.0.6
|
 |
