on my test:
i have esx 5.5u1 and i want copy iso file on local interna datastore ssd
send file iso of 100gb stored on ssd disk with windows 7 64bit "and use webclient or winscp" and speed is 15Mb/s and windows see 12% nic utilization
connect to esx ip managment
il delete esx server and install windows 2012 the copy from w7 and w2012 is 118Mb/s "the switch working perfect"
help me