PQ70665, 5.0: Mandatory Fix for limitation when
using Workflow with Compensation
Downloadable files
Abstract
The mandatory fix for limitation when using Workflow with
Compensation has a few outstanding problems.
Download Description
PQ70665 resolves the following problem:
ERROR DESCRIPTION:
The current (IBM® WebSphere® Application Server 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 an opportunity to allow compensation to
provide a workaround for the >4K LOB problem on Oracle®.
PROBLEM SUMMARY:
USERS AFFECTED: IBM® 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.
PQ70655 WebSphere Application Server V5.0 EE Mandatory Fix for limitation
when using Workflow with Compensation has a few outstanding problems. The
following 4 APARs are currently open against issues that PQ70655 has not
resolved.