PQ71675: V5 - PERFORMANCE PROBLEMS WITH APPLICATION FILTERING

 Fixes are available

5.0.1: WebSphere Application Server Version 5.0 Fix Pack 1 (Version 5.0.1)
5.0.1: WebSphere Application Server Enterprise Edition Version 5.0 Fix Pack 1



APAR status
Closed as program error.

Error description
This apar belongs to: WAS.webui.applicationmanagement
In a test with 100 applications defined in a cell and with 7 app
servers started, a status query used 38 CPU seconds of
processing across the dmgr, node agent and app servers. The time
used is proportional to both the number of defined applications
and the number of started app servers. The production cell
will reach 200 applications and 70 running app servers
this year. The time for a status check in this case would be 20
times larger than this test (2 times the applications and
10 times the started app servers), or 760 CPU seconds. This is
not going to happen, since it would impact the productive work
on all production WebSphere servers while it occurred.
A WebSphere display and deployment system has been developed
for internal use. This system maintains a map of applications to
app servers. It always queries the minimum number of servers to
obtain application status, and has good scaling behavior.
Problems with the application filtering process in the admin gui
magnify this problem. In principle, one could filter to a
single application and then operate only on that application,
avoiding the complete status checks. However, filtering has
design limits and bugs that prevent effective use. These are
listed in the section Problems with Application Filtering
Summarizing the impact: No functions under Enterprise
Applications can be used on a large cell without impacting the
applications in the cell. These funtions cover listing
applications, updating applications, starting and stopping
applications, and viewing and updating properties of
applications. "Install new application"
can be reached without first selecting "Enterprise
Applications", so is still available.
Our experience with our own display and deployment system
demonstrates that these functions can be delivered in a scalable
fashion, but requires use of an application map and stringent
use of filtering. WebSphere gui is not using an application map,
and the filtering function is nearly inoperable.
Problems with Application Filtering
First problem with Application Filtering - The bulk of the
elapsed time and CPU processing used when stopping an
application from the admin gui is due to processing to determine
the status of each application listed. This delay becomes
pronounced with large application counts in a cell.
To attempt to reduce the processing needed to stop and start an
application, I first set filtering to Name followed by the exact
application name and clicked Go. This gave a display with just
one application with a very fast response. However, when I then
selected that app and hit the stop button or start, the return
screen lost filtering, and again determined the status of all
defined applications.
Second problem with Application Filtering - When more than 20
applications are selected the admin determines the status of all
selected applications, even though only the first 20 are
displayed. This is proven by the long response time to return
the first 20 items, and the immediate response time to return
the succeeding panels of 20. For large cells, this long response
makes the admin gui less useful.

Third problem with Application Filtering - There is no way to
select filtering before first calling a full display of
applications. For large cells, one cannot select "Applications >
Enterprise Applications" without impacting all production
WebSphere applications in the cell.
Fourth problem with Application filtering - The only supported
selection fields are application name and application status. We
have added an application developer field that restricts lists
based on the identity of the person making the query. Other
selection fields that could help are app server name and node
name.
Fifth problem with Application Filtering - There is no ability
to list applications without also requesting status.
Sixth problem with Application Filtering - The preferences
button fails, giving null pointer exception. Thus preferences
cannot be utilized.
java.lang.NullPointerException
 at
com.ibm.ws.webcontainer.webapp.WebApp.getRequestDispatcher(WebAp
p.java(Compiled Code))
 at
com.ibm.ws.webcontainer.webapp.WebApp.getRequestDispatcher(WebAp
p.java(Inlined Compiled Code))
 at
org.apache.struts.tiles.ActionComponentServlet.processForward(Ac
tionComponentServlet.java(Compiled Code))
 at
org.apache.struts.tiles.ActionComponentServlet.processActionForw
Local fix Problem summary
****************************************************************
* USERS AFFECTED: All WebSphere Application Server Users       *
****************************************************************
* PROBLEM DESCRIPTION: Performance Problems with               *
*                      Application Filtering                   *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
Diplaying the list of applications from the Admin Console
takes a very long time.
Problem conclusion
Modified Application Management code to improve
performance.
Temporary fix Comments
APAR information
APAR number PQ71675
Reported component name WAS BASE 5.0
Reported component ID 5630A3600
Reported release 00I
Status CLOSED PER
PE NoPE
HIPER NoHIPER
Special Attention NoSpecatt
Submitted date 2003-03-04
Closed date 2003-03-17
Last modified date 2003-03-19

APAR is sysrouted FROM one or more of the following:

APAR is sysrouted TO one or more of the following:

Modules/Macros
WEBUI          

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 > General
Operating system(s):
Software version: 00I
Software edition:
Reference #: PQ71675
IBM Group: Software Group
Modified date: Mar 19, 2003