PK00856; 5.1.1.4: WebSphere Application Server hang
 Downloadable files
 
Abstract
Deadlock when httpconnection class tries to log a message whose text cannot be found and RAS attempts to log message too.
 
Download Description
PK00856 resolve the following problem:

ERROR DESCRIPTION:
The HttpConnection class attempts to log an error message. Its message text can not be found so the RAS code attempts to log a message to the System.out stream, informing about the missing message. However, just before that, the HttpConnection in another thread has started a write to the System.out stream which is redirected to the RAS code.

This causes a deadlock as neither of these threads will be able to continue because they each hold a lock on an object the other one needs.

PROBLEM SUMMARY:

USERS AFFECTED:
IBM® WebSphere® Application Server users of the Http Transport.

PROBLEM DESCRIPTION:
The WebSphere Application Server hangs due to a deadlock between threads in the server process. The deadlock occurs while trying to write an error message and a stack trace.

RECOMMENDATION:
The problem occurs when one thread in HttpConnection tries to write an error message via the RAS component and another thread in HttpConnection tries to write exception to System.out which is redirected thru RAS. Neither of these threads will be able to continue because they each hold a lock on an object the
other one needs.

PROBLEM CONCLUSION:
HttpConnection will be changed to use FFDC to log the exception. This should prevent the deadlock from occurring.

The fix for this APAR is currently targeted for inclusion in V5.0.2.11 and V5.1.1.5.

Please refer to the recommended updates page for delivery information:
General/swg27004980.html
 
Prerequisites
PQ96915
 
URL LANGUAGE SIZE(Bytes)
UpdateInstaller US English 7250000
 
 
Installation Instructions
Please review the readme.txt for detailed installation instructions.
 
URL LANGUAGE SIZE(Bytes)
Readme US English 2426
 
Download package
What is DD?
Download RELEASE DATE LANGUAGE SIZE(Bytes) Download Options
PK00856_5114.jar 6/24/2005 US English 18848 FTP DD
PK00856_511.jar 6/24/2005 US English 18890 FTP DD
PK00856_502_10.jar 6/24/2005 US English 10978 FTP DD
PK00856_502.jar 6/24/2005 UK English 11037 FTP DD
 
Technical support
1-800-IBM-SERV (U.S. Only)
 
Cross Reference information
Segment Product Component Platform Version Edition
Application Servers Runtimes for Java Technology Java SDK
Problems (APARS) fixed
PK00856
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > HTTP Transport
Operating system(s): Windows
Software version: 5.1.1.4
Software edition:
Reference #: 4009949
IBM Group: Software Group
Modified date: Jun 27, 2005