We've been seeing LOADS of these warnings in our logs: -
[16/08/13 08:26:39:608 BST] 00000054 wle W CWLLG2101W: Retries were explicitly requested in ProgrammaticTransactionSupport but no new transaction is started 5 definition: PROPAGATION_REQUIRED,ISOLATION_DEFAULT retryLimit:{2}
As a warning, I had assumed that it was mostly harmless.
This IBM Technote confirms that: -
…
This message is harmless. It is currently showing up in levels of trace where it should not.
Further information: This message is intended to be internal to the components that are using transaction support. If one component calls another component within a transaction context and it specifies a number of retries greater than 0, the message is generated.
Further information: This message is intended to be internal to the components that are using transaction support. If one component calls another component within a transaction context and it specifies a number of retries greater than 0, the message is generated.
…
So it's a niggle, and I wish I didn't appear, but at least I / we can filter it out.