A recovery data flush is a process that the Integration Service uses to flush session recovery data that is in the operating system buffer to the recovery file. You can prevent data loss if the Integration Service is not able to write the recovery data to the recovery file. The Integration Service can fail to write recovery data in cases of an operating system failure, hardware failure, or file system outage. The recovery data flush applies to sessions that include a JMS or WebSphere MQ source and non-relational, non-JMS, or non-WebSphere MQ targets.