Currently, in FileSystemInputPartition, data downloading is implemented in Initilaize() and called from GetPartitionHandle. It doesn't give client a flexibility to decide when to download data. Besides, if client wants to cache data in advance, they need to call GetPartitionHandle() and iterate the data.
We would like to expose a new API Cache() in IInputPartition which performs data download to RAM, SSD, HDD, etc based on client's configuration.
The method should be called in ContextStartHandler in IMRU scenarios.