line items data extraction taking more than a day for just 1 period

Hi,

we are doing a fresh implementation of NW 7.3 and we have a requirement to extract PCA line items from R3 (PCA3 datasource).

while extracting data into infocube, it is taking more than a day just for 1 period containing 35 million records. so, if we go this way looks like, it is going to take few weeks to load all of historical periods. How do we improve this data load time.

appreciate any feedback.