generic function module delta issue

Hi Everyone,

I have created a generic function module datasource (using "RSAX_BIW_GET_DATA" function module) and i have created delta on udate in rso2

And  i am able to extract data for full load  but i am not able to initialize datasource from bw side.Though i am not getting any errors  but the job is running for long time  so i have canceled in sm37.

do i have to make any settings from bw side or from ecc side please suggest.