Optimizing-QoS-vSphere_final

•Burst size is the maximum number
of bytes to allow in a burst. If this
parameter is set, a port might gain a
burst bonus if it does not use all its
allocated bandwidth. Whenever the
port needs more bandwidth than what
is specified by , it
might be allowed to temporarily transmit
data at a higher speed if a burst bonus
is available. This parameter limits the
number of bytes that have accumulated
in the burst bonus and thus transfers at
a higher speed.
Trafcshapingcanprovidebandwidth
limits for a dedicated virtual NIC (vNIC) in
a VM that can use a lot of bandwidth, such
asavNICusedspecicallyforbackup.
Backup can take as much bandwidth as is
available, so to limit the amount available,
the best practice is to create a separate
and dedicated vNIC in the VM and assign
ittoaportgroupthathastrafcshaping
enabled to statically limit the amount of
bandwidth. This practice will allow both
inboundandoutboundtrafcbandwidth
tobelimitedtoaspecicleveltoprovide
predictable backup times and
bandwidth usage.
Note:Trafcshapingisnotsupported
when a dependent hardware iSCSI
adapterisused.Atrafc-shapingpolicyis
denedbythreecharacteristics:average
bandwidth, peak bandwidth, and burst
size.Trafc-shapingpoliciesdonotapply
toiSCSItrafconadependenthardware
iSCSI adapter.
Conclusion
VMwarevSphere4.1representsasignicantevolutioninadministrators’abilitytousevirtualizationtomeet
advanced business needs. Because network connectivity based on 10GbE is a clear necessity to maximize the
valueofthoseadvances,vSphere4.1isspecicallydesignedwithfeaturesthatcomplementIntelEthernet
10 Gigabit Server Adapters. Following the analysis, monitoring, and control best practices presented here will
help administrators take full advantage of 10 Gigabit. Together, vSphere 4.1 and Intel Ethernet 10GbE Server
Adaptersaddanewlevelofperformance,exibility,andintelligencetovirtualizednetworks.
About the Authors
Brian JohnsonisaProductMarketingEngineerfor10GbIntelEthernetProductsatIntelCorporation.Inthisroleheisresponsible
forproductdenition,development,andmarketingof10Gbsiliconproductsalongwithvirtualization,manageability,andsecurity
technologies.Brianhasover15yearsofexperienceinserverproductplanningandmarketing,duringwhichhehasheldvarious
positions in strategic planning, product marketing, and product development.
IntelTechnologyLeaderisaTechnicalMarketingEngineer(TME)forIntelServerI/OVirtualizationandManageability
technologies. As a senior TME, he works with customers, providing both educational materials and answering questions ranging from
technicaltoarchitectural.HehasworkedinnearlyeveryfacetofServerManageability,fromcontributingtotheIPMIspecicationto
writingmanagementsoftwareoveraspanof12yearsatIntel.PatrickhassplithistimebetweenManageabilityandI/OVirtualization
forthepastfouryears.Patrickfrequentlyblogsabouthistechnologiesathttp://communities.intel.com/community/wired.
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