PQ53524: SESSION MANAGER ALWAYS CALLS GETCONNECTION WHEN IT RECEIVES STALECONNECTIONEXCEPTION, CAUSING IT TO LOOP INDEFINATELY


APAR

APAR status
Closed as program error.

Error description
The application is using persistant sessions.  The database goes
down, and the connection manager throws StaleConnectionExceptio
n.  The connection in the pool are marked stale.  The session ma
nager will always call getConnection when it recieves StaleConne
ctionException.  The connection manager recieves the connection
request, purges the pool, and attempts to reconnect.  Since the
database is down, if it maps the database error to a certain sql
state, it will throw StaleConnectionException again.  The sessio
n manager will recieve it and attempt to get a connection
.
The end result is that as long as the database is down, the conn
 mgr and sess mgr are stuck in an endless loop of throwing Stale
ConnectionException and attempting to get a connection.  This ca
uses a spike in CPU utilization, and system performance is affex
ted.
.
To Fix this the session manager needs to either limit the number
 of connection attempts when it recieves StaleConnectionExceptio
n, set an interval between connection attempts, or both.
Local fix
Problem summary
rying to obtain connections if the databas went down and did not
recover immediately.This caused high CPU utilization and the JV
m to crash eventually.
Problem conclusion
tempt to obtain a new connection from the database fails. Now we
try to get a connection only thrice and if no connection is retu
rned we do not perform any database operations.
Temporary fix
Comments
APAR information
APAR numberPQ53524
Reported component nameWAS ADVANCED SU
Reported component ID5648C8402
Reported release350
StatusCLOSED PER
PENoPE
HIPERNoHIPER
Submitted date2001-10-16
Closed date2001-10-30
Last modified date2001-12-18

APAR is sysrouted FROM one or more of the following:

APAR is sysrouted TO one or more of the following:APAR is sysrouted FROM one or more of the following:

PQ56061

Modules/Macros
SESSIONS
APAR is sysrouted TO one or more of the following:PQ56061Modules/Macros

Fix information
Fixed component nameWAS ADVANCED SU
Fixed component ID5648C8402

Applicable component levels
R350 PSYUP











Document Information

Product categories: Software, Application Servers, Distributed Application & Web Servers, WebSphere Application Server, General
Software version: 350
Reference #: PQ53524
IBM Group: Software Group
Modified date: 2001-12-18