code: def rpc_chain_sync(server_state, new_block_height, finish_time):
      
      rpc_srv = server_state['rpc']
      if rpc_srv is not None:
          rpc_srv.cache_flush()
          rpc_srv.set_last_index_time(finish_time)
docs: Flush the global RPC server cache, and tell the rpc server that we've
      reached the given block height at the given time.