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MSMCAEvent_SwitchToCMCPolling class

The MSMCAEvent_SwitchToCMCPolling class represents the corrected machine check (CMC) handling to be switched from the interrupt driver to polling. In some cases, the kernel polls the system abstraction layer (SAL) for any CMC or corrected platform error (CPE) that occurred within the previous polling interval. This class is available only in 64-bit Windows systems.

The following syntax is simplified from Managed Object Format (MOF) code and includes all of its inherited properties. Properties and methods are in alphabetic order, not MOF order.


class MSMCAEvent_SwitchToCMCPolling : WMIEvent
  boolean Active;
  string  InstanceName;


The MSMCAEvent_SwitchToCMCPolling class has these types of members:


The MSMCAEvent_SwitchToCMCPolling class has these properties.

Data type: boolean
Access type: Read-only

TRUE, if this instance of the class is active; otherwise, FALSE.

Data type: string
Access type: Read-only
Qualifiers: Key

Unique identifier of this instance of the class.


The MSMCAEvent_SwitchToCMCPolling class is derived from WMIEvent.

The system abstraction layer (SAL) is code burned onto ROM that the operating system calls to perform platform-dependent operations. It is similar to the BIOS on an x86 platform. In cases where the platform does not support interrupts for CMC or CPE polling, the operating system polls every minute, checking if an error occurred previously. If the platform does support interrupts and the operating system receives a user defined amount of CMC or CPE polls within one minute, then it disables the interrupt and poll. If the user does not define the number of polls within one minute, the system sets a default to 10 polls per minute.


Minimum supported client

Windows XP

Minimum supported server

Windows Server 2003







See also

MSMCA Classes



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