WebSphere Application Server - DB2 RS Transaction Isolation Level is Default

In WebSphere, the default transaction level is set to something very restrictive.

It’s likely that they haven’t changed this in their app server configuration.

Have them check the webSphereDefaultIsolationLevel custom property on their data sources.

https://www.ibm.com/support/pages/determining-and-changing-isolation-level

“If the database connection is obtained in a servlet, JSP, or session bean, TRANSACTION_REPEATABLE_READ is used by default.”

JDBC Isolation Level

              

DB2 Isolation Level

TRANSACTION_SERIALIZABLE      Repeatable Read (RR)

TRANSACTION_REPEATABLE_READ           Read Stability (RS)  ← Deafult

TRANSACTION_READ_COMMITTED          Cursor Stability (CS) ← What we want

TRANSACTION_READ_UNCOMMITTED    Uncommitted Read (UR)

“In WebSphere Application Server V6.1 and above, the webSphereDefaultIsolationLevel custom property can be set on a data source to change the default isolation level that is used even if indirect JNDI lookups and resource references are not used by the application.”

Procedure for changing this setting in WAS 8.5.5 can be found here:
https://www.ibm.com/support/knowledgecenter/en/SSWLGF_8.5.6/com.ibm.sr.doc/twsr_setwebspheredefaultisolationlevelproperty.html