regarding background process
SAP offers a solution to the "short nights" problem: parallel-processed background jobs. Long-running reports can now implement parallel processing, which lets them parcel out the work to be done to available work processes and then collect and synchronize the results. so in these cases we have to split the variants and
process the report parallel. for that we have to develop a wrapper program for a main program . so any body developed such kind of reports.
for example if a report needs to get data for 1 year you need to split the variant in 12 months and run them parallel