Product : Citrix, XenServer/7.3, Enterprise
Feature : Offload Support, Networking, Network and Storage
Content Owner:  Roman Macek
Summary
Yes (TSO)
Details
TCP Segmentation Offload can be enabled, see http://bit.ly/13e9WLi
By default, Large Receive Offload (LRO) and Generic Receive Offload (GRO) are disabled on all physical network interfaces. Though unsupported, you can enable it manually http://bit.ly/2djwZiZ