Autosave: investigate whether autosave can be split up within IOCs

[Tom-Willemsen]

It would be helpful to be able to have separate autosave files for different axes/sensors on various IOCs. This would be a more general solution to the problem addressed in https://github.com/ISISComputingGroup/IBEX/issues/2831.

The IOCs which stand out as particularly relevant for this are the ones which define a variable number of DB records, such as:

• Galil axes
• Eurotherm sensors
• Mk3 choppers
• Genesys
• Danfysik

This ticket should investigate whether this is possible and document the mechanism to do it. If it is possible, a new ticket should be created to do this on all the relevant IOCs.

[AdrianPotter]

The workflow where this would be helpful is as follows:

• Imagine you have a chopper that autosaves values per channel
• You have two configurations, one with 2 channels, the other with 1 channel
• When you run in the 2 channel configuration, autosave values are captured for both channels
• When you run with 1 channel, only its channels are autosaved
• When you switch back to having 2 channels, the 2nd channel has no autosaved values so the old values are lost.

This issue applies to any IOC where the available PVs varies depending on configuration.