PQ70895; 4.0.4, 4.0.5: POST data read after IOTimeout
 Downloadable files
 
Abstract
Web container attempts to read POST data after IOTimeout
 
Download Description
PQ70895 resolves the following problem:

USERS AFFECTED:
WebSphere® Application Server users experiencing connection time-outs when servicing HTTP Requests.

PROBLEM DESCRIPTION:
WebSphere outputs an error message to the logs indicating a connection time-out in attempting to read POST data sent from a client. At the end of a POST request, WebSphere attempts to read from the client any remaining POST data that was sent by the client. If an IOException occurs during the reading of the POST data (when parsing the original POST data), WebSphere should not attempt to read the POST data again since the client socket is no longer accessible to read data from. When an IO occurs when reading in POST data, WebSphere will attempt to read the post data a second time when finishing the connection.

PROBLEM CONCLUSION:
The code was modified to limit the possibility of this IOException from occurring. WebSphere will now track if an IOException occurs when reading in the original POST data and not try to read from the socket when this occurs.

Another possible circumvention for this problem is to change the keep-alive timeout. (i.e. increasing the default value).

Each system is unique and has different optimum parameter settings. These are reasonable values for Web Container HTTP transport settings:

MinThreadSize = MaxThreadSize = 50 (defaults are 25 and 50)
KeepAlive Timeout = 10 - 60 (default is 5)
I/O Timeout = 10 - 60 (default is 5)
Do not enable thread allocation beyond maximum (increase MinThreadSize and MaxThreadSize if needed)

General recommendation is to set I/O and KeepAlive timeout to the same or lower values as their corresponding parameters in Web server, such as Timeout and KeepAliveTimeout in IHS or Apache. Results of performance tests should show optimum parameters for HTTP transport of the Servlet Engine.

NOTES:
This interim fix should be applied to WebSphere Application Server system.
 
Prerequisites
None
 
 
Installation instructions
Please review the readme for detailed installation instructions.
 
URL LANGUAGE SIZE(Bytes)
Readme US English 3885
 
Download package
What is DD?
DOWNLOAD RELEASE DATE LANGUAGE SIZE(Bytes) Download Options
PQ70895 2/12/2003 US English 869941 FTP DD
 
Technical support
800-IBM-SERV (U.S calls only)
 
Problems (APARs) fixed
PQ70895
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > Servlet Engine/Web Container
Operating system(s): HP-UX
Software version: 4.0.5
Software edition:
Reference #: 4004451
IBM Group: Software Group
Modified date: Mar 28, 2003