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IVssProviderCreateSnapshotSet::CommitSnapshots method (vsprov.h)

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The CommitSnapshots method quickly commits all LUNs in this provider.

Syntax

HRESULT CommitSnapshots(
  [in] VSS_ID SnapshotSetId
);

Parameters

[in] SnapshotSetId

The VSS_ID that identifies the shadow copy set.

Return value

Return code/value Description
S_OK
0x00000000L
 The operation was successfully completed.
E_OUTOFMEMORY
0x8007000EL
 Out of memory or other system resources.
E_INVALIDARG
0x80070057L
 One of the parameter values is not valid.
VSS_E_OBJECT_NOT_FOUND
0x80042308L
 The SnapshotSetId parameter refers to an object that was not found.
VSS_E_PROVIDER_VETO
0x80042306L
 An unexpected provider error occurred. The provider must log the details of this error in the application event log.
 

If any other value is returned, VSS will write an event to the event log and convert the error to VSS_E_UNEXPECTED_PROVIDER_ERROR.

Remarks

This method is called at the defined time at which the shadow copies should be taken. For each prepared LUN in this shadow copy set, the provider will perform the work required to persist the point-in-time LUN contents. While this method is executing, both applications and the I/O subsystem are largely quiescent. The provider must minimize the amount of time spent in this method. As a general rule, this method should take less than one second to complete. This method is called during the Flush and Hold window, and VSS Kernel Support will cancel the Flush and Hold if the release is not received within 10 seconds, which would cause VSS to fail the shadow copy creation process. If each provider takes more than a second or two to complete this call, there is a high probability that the entire shadow copy creation will fail.

Because the I/O system is quiescent, the provider must take care to not initiate any I/O as it could deadlock the system - for example debug or tracing I/O by this method or any calls made from this method. Memory mapped files and paging I/O will not be frozen at this time.

Note that the I/O system is quiescent only while this method is executing. Immediately after the last provider's CommitSnapshots method returns, the VSS service releases all pending writes on the source LUNs. If the provider performs any synchronization of the source and shadow copy LUNs, this synchronization must be completed before the provider's CommitSnapshots method returns; it cannot be performed asynchronously.

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Target Platform Windows
Header vsprov.h

See also

IVssProviderCreateSnapshotSet