1. Only one available backend. 2. All backends are checked but this round is not changed. For example, all backends are on the same host.
# fe-common This module is used to store some common classes of other modules. # spark-dpp This module is Spark DPP program, used for Spark Load function. Depends: fe-common # fe-core This module is the main process module of FE. Depends: fe-common, spark-dpp