The Journal Write Cycle The Journal Write Cycle The operation that writes the contents of the journal buffer to the journal file is called a journal sync. A journal sync is guaranteed to write all operations currently in the journal buffer to the current journal file.The frequency with which the journal is synced depends on the operating circumstances of the InterSystems IRIS instance involved. A journal sync can be triggered: Once every two (2) seconds if the system is idle. In an ECP-based distributed cache cluster, by the data server when responding to specific requests (for example, $Increment) from the application servers to guarantee ECP semantics. By a TCOMMIT (in synchronous commit mode, which causes the data involved in that transaction to be flushed to disk) if you are using InterSystems IRIS transactions. As part of every database write cycle by the write daemon. When the journal buffer is full.
