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VM metricsMemory ActiveUnits: KBInternal Name: activeAmount of guest physical memory recently used by theVM, which is estimated by VMkernel statistical sampling.Memory BalloonUnits: KB

Internal Name: vmmemctl

Amount of guest physical memory that is currentlyreclaimed from the VM throughballooning.This is the amount of guest physical memory that hasbeen allocated and pinned by theballoon driver.Memory Balloon TargetUnits: KBInternal Name: vmmemctltargetDesired value for the VMs Memory Balloon, asdetermined by the VMkernel.

The VMkernel sets a target for the level of balloonedmemory for each VM, based on anumber of factors. IfMemory Balloon Target is greater than Memory Balloon,the VMkernel willinflate the balloon, causing more VMmemory to be reclaimed and Memory Balloonto increase.If Memory Balloon Target is less than Memory Balloon,theVMkernel will deflate the balloon, allowing the VM tomap/consume additional memoryif it needs it. MemoryBalloon will decrease as the VMkernel deflates theballoon.

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Memory ConsumedUnits: KBInternal Name: consumedAmount of machine memory allocated to the VM,accounting for savings from memorysharing with otherVMs. Memory Overhead is not included.When multiple VMs are sharing a single region of machinememory, each VM ischarged for the memoryproportionally based on the total references to that regionofshared memory. For instance, if a VM has 100 MB ofmemory that is shared equallywith three other VMs, thenthat VMs portion of the shared memory is only 25 MB(100MB / 4 VMs) for the Memory Consumed statistic.Because Memory Consumed measures a VMs use ofmachine memory, it should beused for issues such aschargeback.See the Differences between Memory Granted/Sharedand MemoryShared/Shared Common section for moreinformation on this statistic.Memory GrantedUnits: KBInternal Name: grantedAmount of guest physical memory currently mapped to(i.e., backed by) machinememory. Memory Overhead isnot included, but Memory Shared is.Note that this is notthe amount of machine memory usedby the VM; MemoryConsumed measures a VMs machinememory usage.See the Differences between Memory Granted/Sharedand MemoryShared/Shared Common section for moreinformation on this statistic.

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Memory OverheadUnits: KBInternal Name: overhead

Extra machine memory used by the VMkernel to run theVM. For more information onmemory overhead.Since Memory Overhead always resides in machinememory, the VMkernel mustreserve memory for the VMsoverhead memory. Thus a VMs memory reservation hastwo components: a user-specified memory reservationand the overhead memoryreservation (i.e. MemoryOverhead).

For example, if the user specified a 1 GBreservation andthe Memory Overhead for the VM is 100 MB, then theVMs memoryreservation when powered on would be 1.1GB.Memory SharedUnits: KBInternal Name: sharedAmount of guest physical memory shared throughtransparent page sharing. It includesMemory Zero.Transparent page sharing is a method of RAM de-duplication.Memory Swap InUnits: KBInternal Name: swapinTotal amount of memory data that has been read in fromthe VM's swap file to machinememory by the VMkernelsince the VM powered on. This statistic refers to VMkernelswapping and not to guest OS swapping.Memory Swap Out

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Units: KBInternal Name: swapoutTotal amount of memory data that has been written out tothe VM's swap file frommachine memory by the VMkernelsince the VM powered on. This statistic refers toVMkernelswapping and not to guest OS swapping.Memory Swap TargetUnits: KBInternal Name: swaptargetDesired value for the VMs Memory Swap, as determinedby the VMkernel.The VMkernel sets a target for the levelof swapping for each VM, based on a number offactors. IfMemory Swap Target is greater than Memory Swap, thenthe VMkernel will start swapping,causing more VMmemory to be swapped out. This will generally happenquickly. IfMemory Swap Target is less than MemorySwap, then the VMkernel will stopswapping. Sinceswapped memory stays swapped until the VM accesses it,MemorySwapped can be greater than Memory SwapTarget, possibly for a prolongedperiod of time. This simplymeans that the swapped memory is not currently neededbythe VM and is not a cause for concern.Memory SwappedUnits: KB

Internal Name: swappedCurrent amount of guest physical memory swapped out tothe VMs swap file by theVMkernel. This statistic refers toVMkernel swapping and not to guest OS swapping.Memory UsageUnits: Percent

Internal Name: usage

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Memory Active / VM memory configured size.Memory ZeroUnits: KBInternal Name: zeroAmount of guest physical "zero memory" that is sharedthrough transparent page sharing."Zero memory" is simply memory that is all zeroes. Thisstatistic is included in MemoryShared. Transparent pagesharing is a method of RAM de-duplication.

Host metricsMemory ActiveUnits: KB

Internal Name: activeSum of Memory Active of all powered on VMs andVMware Infrastructure serviceson the host.Memory BalloonUnits: KBInternal Name: vmmemctlSum of Memory Balloon of all powered on VMs andVMware Infrastructure serviceson the host.Memory ConsumedUnits: KBInternal Name: consumedAmount of machine memory used on the host. It includesService Console memory,VMkernel memory, VMware

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Infrastructure services memory and VM memory.Memory GrantedUnits: KBInternal Name: grantedSum of Memory Granted of all powered on VMs andVMware Infrastructure serviceson the host. Since eachVMs Memory Granted measures its guest physicalmemory, the hostsMemory Granted may be larger thanthe amount of machine memory if memory isovercommitted (i.e. aggregate VM configured memory is

greater than machine memory).Memory HeapUnits: KBInternal Name: heapAmount of VMkernel virtual address space dedicated toVMkernel main heap and relateddata. Memory Heap ishardcoded at 30 MB for ESX 3.5U2. This space is used bytheVMkernel for some of its memory plus memory formodules and device drivers. Usersshould not worry aboutthis statistic.Memory Heap FreeUnits: KBInternal Name: heapfreeAmount of free machine memory on the VMkernel's mainheap.Memory Heap Free will vary depending on theamount of physical devices and variousconfigurationoptions. There is no direct way for the user to increase ordecrease thisstatistic. Users should not worry about thisstatistic.Memory Overhead

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Units: KBInternal Name: overheadSum of Memory Overhead of all powered on VMs andVMware Infrastructureservices on the host.Memory Reserved CapacityUnits: MBInternal Name: reservedCapacityTotal amount of memory reservation used by powered onVMs and VMwareInfrastructure services on the host,which includes Memory Overhead. Since thisstatisticincludes Memory Overhead, it will be greater than zeroeven when nopowered on VM has a user-specifiedreservation (due to the fact that all powered on VMsrequire some overhead memory).Memory SharedUnits: KB

Internal Name: sharedSum of Memory Shared of all powered on VMs andVMware Infrastructure serviceson the host. Since eachVMs Memory Shared measures guest physical memory,the hostsMemory Shared may be larger than the amountof machine memory if memory ishighly overcommitted(i.e. aggregate VM configured memory is much greater

thanmachine memory). This illustrates how effectivetransparent page sharing and memoryovercommitment are for saving machine memory.Memory Shared CommonUnits: KBInternal Name: sharedcommonAmount of machine memory that is shared by powered on

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VMs and VMwareInfrastructure services on the host.Memory Shared - Memory Shared Common = memorysavings for the host fromsharing.