Update 4 introduced an adaptive queue depth algorithm from the ESX host. by default, this algorithm is disabled.
So if the setting is disabled what should the Qdepth be for HBA.
From what I understand from the feature , this helps avoid over congestion to single luns from multiple ESX hosts . Also all hosts must have this feature enabled in order to use it . Lets say that X hosts have it enabled and Y hosts dont have it configured . The Y hosts may consume the resources/slots on the array that are freed up by the adaptive hosts.
I also see that 3 par is the one that has pushed this enhancement for esx3.5 u4 . Is this because 3 par is the only one that has issues with supporting a qdepth larger than 32 for multiple esxhost and Virtual machines ??
see
http://www.3par.com/news_events/20090421.html
and
Vmware KB Article: 1008113
"This algorithm was well tested against 3PAR arrays and hence limiting the configuration to 3PAR arrays only for now."
so that being said . If im guaranteeing a qdepth of 128 for High I/O workloads because I have sized the netapp for the correct amount of HBA's for eaxh esx server would i even need to employ the adaptive queue depth algorithm from the ESX host for NetApp??