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IVMGuestOS::IsHeartbeating property

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[Windows Virtual PC is no longer available for use as of Windows 8. Instead, use the Hyper-V WMI provider (V2).]

Determines whether the virtual machine has a heartbeat.

This property is read-only.

Syntax

HRESULT get_IsHeartbeating(
  [out, retval] VARIANT_BOOL *heartBeating
);

Property value

VARIANT_TRUE if a heartbeat is detected, VARIANT_FALSE otherwise.

Error codes

Name/value Meaning
S_OK
0
 The operation was successful.
E_POINTER
0x80004003
 The parameter is NULL.
VM_E_VM_UNKNOWN
0xA0040207
 The configuration is unknown.
VM_E_VM_NOT_RUNNING
0xA0040206
 The virtual machine must be running for this operation.
VM_E_ADDITIONS_NOT_AVAIL
0xA0040504
 The virtual machine is not fully booted, the integration components feature is not installed, or the installed version does not support this feature.
DISP_E_EXCEPTION
0x80020009
 An unexpected error has occurred.

Remarks

When integration components is installed in the guest operating system, a regular 'tick' or heartbeat is sent from the virtual machine session to Windows Virtual PC. If the guest operating system is heavily loaded, it's possible that Virtual PC will receive fewer heartbeats than expected. If no heartbeat is detected, it is possible that the guest operating system is not responding or is crashed.

By default, a virtual machine produces ten heartbeat ticks per minute. If no heartbeat ticks are detected for an entire minute, Windows Virtual PC will attempt to restart the virtual machine session once every ten seconds for up to two minutes. This behavior is controlled by the following key values in the virtual machine session's configuration file.

Configuration key Default Description
integration/microsoft/heartbeat/time
 60
 The length of the block of time used to generate heartbeat ticks, in seconds.
integration/microsoft/heartbeat/rate
 10
 The number of ticks generated in each heartbeat time block.
integration/microsoft/heartbeat/failure_interval
 10
 The number of seconds between restart attempts, once no heartbeat ticks are received within a specific heartbeat time block.
integration/microsoft/heartbeat/failure_attempts
 12
 The number of restart attempts made.

Requirements

Requirement Value
Minimum supported client
 Windows 7 [desktop apps only]
Minimum supported server
 None supported
End of client support
 Windows 7
Product
 Windows Virtual PC
Header
VPCCOMInterfaces.h
IID
 IID_IVMGuestOS is defined as 99fea0db-4880-499a-b6d8-73dff9bc91be

See also

IVMGuestOS