PQ70665: SUPPORT INFINITE COMPENSATABLE STEPS IN A FLOW

 Fixes are available

PQ70665, 5.0: Mandatory Fix for limitation when using Workflow with Compensation
5.0.1: WebSphere Application Server Enterprise Edition Version 5.0 Fix Pack 1



APAR status
Closed as program error.

Error description
The current (v5.0) implementation of compensation has two
serious limitations:
1. The number of compensatable steps per flow is finite (in the
   case of Cloudscape and DB2 backends, the limit is around
   15,000 steps)
2. As the number of compensatable steps in a flow increases,
   the pathlength and JVM memory required to record new steps
   increases linearly. Hence as a flow increases in size, its
   performance currently has an O(n2) factor introduced to it
   by the compensation support.
This is caused by all of the compensatable steps being stored
within a single BLOB. This APAR removes the two limitations by
moving the information into its own database table.  In
addition, since this APAR requires a change to the Database
schemas used by compensation, it provides a opportunity to
allow compensation to provide a workaround for the >4K LOB
problem on Oracle.
Local fix Problem summary
****************************************************************
* USERS AFFECTED: WebSphere Application Server users of        *
*                 compensation facility of Business Processes. *
****************************************************************
* PROBLEM DESCRIPTION: The number of compensatable steps per   *
*                      flow is finite.                         *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
The number of compensatable steps per flow is finite (in the
case of Cloudscape and DB2 backends, the limit is around
15,000 steps). As the number of compensatable steps in a flow
increases, the pathlength and JVM memory required to record
new steps increases linearly. Hence as a flow increases in
size, its performance currently has an O(n2) factor introduced
to it by the compensation support.
Problem conclusion
The compensation facility will be modified to allow an infinite
number of compensatable steps in a flow.
Temporary fix Comments
APAR information
APAR number PQ70665
Reported component name WAS ENTERPRISE
Reported component ID 5630A3700
Reported release 00W
Status CLOSED PER
PE NoPE
HIPER NoHIPER
Special Attention NoSpecatt
Submitted date 2003-02-05
Closed date 2003-05-27
Last modified date 2003-05-27

APAR is sysrouted FROM one or more of the following:

APAR is sysrouted TO one or more of the following:

Modules/Macros
compenst          

Publications Referenced

Fix information

Applicable component levels
R003 PSY    UP
R00A PSY    UP
R00H PSY    UP
R00I PSY    UP
R00S PSY    UP
R00W PSY    UP


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > Enterprise Edition (EE)
Operating system(s):
Software version: 00W
Software edition:
Reference #: PQ70665
IBM Group: Software Group
Modified date: May 27, 2003