Risks of Using delayed_commit

When you enable set delayed_commit, SAP ASE notifies the client application before the actual physical disk write completes.

Because of this, the application perceives that the transaction is complete whether or not the physical disk write is successful. In the event of a system failure (disk errors, system crash, and so on), transactions that were not written to disk (transactions whose commit records were on the last log page) are not present after recovery in spite of the application being notified they were committed.

Systems that require tight system interdependencies, such as through a messaging system using Real Time Data Services (RTDS), further complicate the consequences of using set delayed_commit.

There are two situations where applications can manage the risk: