Hi Sumedh.

Judging by the numbers (25 GB, 17GB), I assume that there is a very huge data set you are trying to download without enough pre-filtering.
CDF is not a file, so it’s not something that is easy to pull in one go.

To make this fast you’d need to use server-side (push-down) filters.
It is recommended selecting a subset of data by filtering the resources by specific fields (E.g. externalId, data set id, etc).

More about push-down filters: https://docs.cognite.com/cdf/dashboards/guides/powerbi/filtering#assets

More hints on performant queries:
https://docs.cognite.com/cdf/dashboards/guides/powerbi/best_practices#performance-best-practices