Journal Freeze on Error Setting is Yes
If you configure InterSystems IRIS to freeze on a journal file I/O error, all journaled global updates are frozen immediately upon such an error. This prevents the loss of journal data at the expense of system availability. Global updates are also frozen if the journal daemon has been unable to complete a journal write for at least 30 seconds.
The journal daemon retries the failed I/O operation and unfreezes global updates after it succeeds. Meanwhile, the freezing of global updates causes other jobs to hang. The typical outcome is that InterSystems IRIS hangs until you resolve the journaling problem, with the system appearing to be down to operational end-users. While InterSystems IRIS is hung you can take corrective measures, such as freeing up disk space, switching the journal to a different disk, or correcting a hardware failure.
The advantage to this option is that once the problem is resolved and InterSystems IRIS resumes normal operation, no journal data has been lost. The disadvantage is that the system is less available or unavailable while the problem is being solved.
InterSystems IRIS posts alerts (severity 3) to the messages.log file periodically while the journal daemon is retrying the failed I/O operation.
