Automatic event-queue reset

If an event-queue file becomes corrupt, Data Archive automatically resets the event queue to attempt to recover data. In many situations, automatic event-queue reset can keep events flowing, even if an unexpected error occurs while Data Archive reads or writes to the event queue. It is supported for both historic and future event queues.

Note: The event queue serves as a memory and disk buffer between the snapshot subsystem and archive subsystem. For more information, see Event queue.

If Data Archive detects corruption in the event queue, it attempts to recover the existing event-queue files. If recovery fails, Data Archive moves the event-queue files to a new folder and creates a new queue. The new folder is a sub-folder of the main event-queue folder; its name includes a time stamp.

Note: The location of the main event-queue folder is set during installation or upgrade. For more information, see the Data Archive installation topic, Determine the disk volumes for your deployment.

If you need to recover the old event-queue files, contact AVEVA Technical Support.

Data Archive writes message ID 2378 to the log file when it attempts automatic event-queue reset, and writes further messages to record the success or failure of the operation.

The following performance counters record information about automatic event-queue reset.

For lists of other performance counters that gather statistics, see the Data Archive reference topic, PI performance counters.