I have noticed that with VSC 4.1, in the vsc.log, the Disk.QFullSampleSize and Disk.QFullThreshold values are ignored for ESXi 5.1 hosts.
Excerpts from vsc.log:
Quietly ignoring Disk.QFullSampleSize value from host because host is version [5.1.0]
Quietly ignoring Disk.QFullThreshold value from host because host is version [5.1.0]
I understand that the original release of ESXi 5.1 did not support globally setting Disk.QFullSampleSize and Disk.QFullThreshold values, but we have installed ESXi510-201212001 which adds back the ability to set these values globally (see http://kb.vmware.com/kb/2035777). It appears that VSC 4.1 assumes that any patch release of ESXi 5.1 does not support these values. Is there a way to override this behavior of VSC 4.1?
By default, VSC doesn't automatically set any host settings. Right-click the 5.1 host with the patch, select "Set Recommended Settings", then select "Adapter Settings".
Can you send me all the VSC logs (vsc.log/nvpf/log/wrapper/log/ehuSettings.dat)? The log message you are seeing is printed when either the VSC default setting is either not the ehuSettings.dat file or the QFull setting does not exist on the host. Therefore, please verify the patch is installed on the host. I don't recall if the host has to be rebooted after installing the patch.
Re: QFullSampleSize and QFullThreshold values ignored by VSC 4.1 for ESXi 5.1 hosts