iSCSI Clients Commands Time Interval Statistic

What is command time interval:

Client delays its response at the application layer for an unacceptable amount of time despite acknowledging receipt of traffic at the TCP layer from server.

Scenario 1:

Broadcom VMware ESXi

VMware/broadcom KB 313806 talks about similar thing:

https://knowledge.broadcom.com/external/article/313806/send-and-receive-buffer-sizes-of-the-tcp.html

"Host is reporting Calculated Window Size: 514 bytes. This indicates a very small TCP receive buffer on the host. A window size of 514 bytes is abnormally low and could severely limit throughput."