We just did a fresh install of ESXi 5 on a host that was running ESX 4 before. Nothing has changed hardware wise. After the upgrade network performance is much slower. Even copying a big file from one VM to another VM within same virtual switch is slower compared to other hosts that are running ESX 4.
Network cards are auto-negotiating at 1Gbps as were on ESX 4 prior to upgrade. All settings are default and I haven't played with Advanced Settings at all.
Before opening a case with vmware, wanted to know if I am missing something or if others have experienced similar issues and found a fix?