Fix (APAR):  PK20141

Status:  Fix

Release:  6.0.2.8,6.0.2.7,6.0.2.6,6.0.2.5,6.0.2.4,6.0.2.3,6.0.2.2,6.0.2.1,6.0.2

Operating System:  AIX,HP-UX,i5/OS,Linux,Linux pSeries,Linux Red Hat - pSeries,Linux zSeries,OS/390,OS/400,Solaris,Windows,z/OS

Supersedes Fixes:  

CMVC Defect:  347435

Byte size of APAR:  9104

Date: 2006-07-25

Abstract:  LaunchClient may timeout because of a hang issue with a large number of client requests coming in when no servers are available to service the requests.

Description/symptom of problem:  
PK20141 resolves the following problem:

ERROR DESCRIPTION:                                              
The issue here is that if a large number of client requests are 
sent in a short period of time, each of them will spawn a       
callback thread.  The large number of threads can cause issues  
with the client starting up and it may timeout.                 
                                                                
In a java core you would see a thread holding a lock on         
com.ibm.ws.wpf.selection.PartitionedProxyImpl@10A72B30          
and waiting at com.ibm.ws.cluster.router.selection.             
BridgeSynchClientToSynchAndAsynchSelectionService.select(:131)  
                                                                
This function takes 1 second for each thread coming into it,    
the solution was removal of all references to the BridgeSynch   
function.                                                       

LOCAL FIX:                                                      

PROBLEM SUMMARY

USERS AFFECTED:
WebSphere Application Server users of
version 6.0.2 with a high client request
volume.

PROBLEM DESCRIPTION:
LaunchClient may timeout because of a
hang issue with a large number of
client requests coming in when no
servers are available to service the
requests.

RECOMMENDATION:
None

The BridgeSynchClientToSynchAndAsynchSelectionService causes
a 1 second delay on each incoming request which cannot be
serviced by a server.  This function has been looked at for
possible removal because this 1 second delay is not
necessary.  This APAR implements the removal of this
function.


PROBLEM CONCLUSION:                                             
The single reference to the                                     
BridgeSynchClientToSynchAndAsynchSelectionService was removed   
                                                                
The fix for this APAR is currently targeted for inclusion       
in fixpack 6.0.2.9.                                             
Please refer to the recommended updates page for delivery       
information:                                                    
http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980   
                                                                

Directions to apply fix:  NOTE: Choose the:
1) Release the fix applies to
2) The Editions that apply
3) Delete the Editions & Methods that do not apply and this Note

Fix applies to Editions:
Release 6.0
__ Application Server (Express or BASE)
__ Network Deployment (ND)
__ WebSphere Business Integration Server Foundation (WBISF)
__ Edge Components
__ Developer
__ Extended Deployment (XD)

Install Fix to:
Method:
__ Application Server Nodes
__ Deployment Manager Nodes
__ Both

NOTE:
The user must:
* Have Administrative rights in Windows, or be the Actual Root User in a UNIX environments.
* Logged in with the same authority level when unpacking a fix, fix pack or refresh pack.
* Be at V6.0.2.2 or newer of the Update Installer. This can be checked by reviewing the level of the Update Installer in file <was_root>/updateinstaller/version.txt.

The Update Installer can be downloaded from the following link:
http://www.ibm.com/support/docview.wss?rs=180&uid=swg21205991

For detailed instructions to Extract the Update Installer see the following Technote:
http://www-1.ibm.com/support/docview.wss?rs=180&uid=swg21205400

1) Copy PKxxxxx.pak file directly to the maintenance directory

2) Shutdown WebSphere
Manually execute setupCmdLine.bat in Windows or . ./setupCmdLine.sh in Unix from the WebSphere instance that maintenance is being applied to.

3) Launch Update Installer

4) Enter the installation location of the WebSphere product you want to update.

5) Select the "Install maintenance package" operation.

6) Enter the file name of the maintenance package to install (PKxxxxx.pak file which was copied in the maintenance directory).

7) Install the maintenance package.

8) Restart WebSphere

Directions to remove fix:  NOTE:
* The user must have Administrative rights in Windows, or be the Actual Root User in a UNIX environments.
* FIXES MUST BE REMOVED IN THE ORDER THEY WERE APPLIED
* DO NOT REMOVE A FIX UNLESS ALL FIXES APPLIED AFTER IT HAVE FIRST BEEN REMOVED
* YOU MAY REAPPLY ANY REMOVED FIX

Example: If your system has fix1, fix2, and fix3 applied in that order and fix2 is to be removed, fix3 must be removed first, fix2 removed, and fix3 re-applied.

1) Shutdown WebSphere
Manually execute setupCmdLine.bat in Windows or . ./setupCmdLine.sh in Unix from the WebSphere instance that uninstall is being run against.

2) Start Update Installer

3) Enter the installation location of the WebSphere product you want to remove the fix.

4) Select  "Uninstall maintenance package" operation.

5) Enter the file name of the maintenance package to uninstall (PKxxxxx.pak).

6) UnInstall maintenance package.

7) Restart WebSphere

Directions to re-apply fix:  1) Shutdown WebSphere.

2) Follow the Fix instructions to apply the fix.

3) Restart WebSphere.

Additional Information: