Hi,
There are umpteen number of documents available for the same.
Please find couple of white papers below where you will find more details about fabric path and the benefits it provides among other technologies.
http://www.cisco.com/c/en/us/products/collateral/switches/nexus-5000-series-switches/white_paper_c11-709336.html
http://www.cisco.com/c/en/us/products/collateral/switches/nexus-7000-series-switches/white-paper-c11-737022.html
Regards,
Sunil.