Environment (Required on creation):

Any still supported Camunda 7 version.

Description (Required on creation; please attach any relevant screenshots, stacktraces, log files, etc. to the ticket):

• High amounts of history were produced in the past
• Producing history is temporarily disabled by changing the history level to NONE
  • Reason: performance of process execution is degraded due to high amounts of history data
• A removal time should be assigned to the history data to clean it up
• The batch operation to set a removal time to historic process instances doesn't work since the history level is configured to NONE

Steps to reproduce (Required on creation):

• Configure the history level to FULL
• Start a process instance
• Configure the history level to NONE
• Perform the batch operation "Set removal time to process instances" on the historic process instance

Observed Behavior (Required on creation):

The removal time is not set.

Expected behavior (Required on creation):

Removal time is set.

Root Cause (Required on prioritization):

The historic process instance query returns an empty list when the history level is configured to NONE [1].

Solution Ideas (Optional):

1. Introduce a new built-in history level that doesn't produce history but allows to perform queries.
   • Cons
     • Cockpit might not be usable since history queries take a very long to return
2. Register a custom history level that doesn't produce history but allows to perform queries.
   • Cons
     • User needs to write custom code
3. Prevent disabling history queries for batch operations needed for history cleanup.
   • Cons
     • There might be other scenarios in which querying for history data is beneficial that cannot be achieved with this solution

Hints (optional):

-

[1] https://github.com/camunda/camunda-bpm-platform/blob/master/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/HistoricProcessInstanceManager.java#L106