IDedupReadFileCallback::OrderContainersRestore method (ddpbackup.h)
This method provides the application with the ability to influence the order of the pending reads that are required to retrieve the target file.
Given a list of container files that hold data for the restore target file, generates a list of container file extents in a sorted order that results in an efficient cross-container read plan from the backup store.
Implementation of this method by the application is optional.
Syntax
HRESULT OrderContainersRestore(
[in] ULONG NumberOfContainers,
[in] BSTR *ContainerPaths,
[out] ULONG *ReadPlanEntries,
[out] DEDUP_CONTAINER_EXTENT **ReadPlan
);
Parameters
[in] NumberOfContainers
Number of container paths in the ContainerPaths array.
[in] ContainerPaths
Array of paths to container files that must be read in order to restore the file specified in the IDedupBackupSupport::RestoreFiles call. Each element is a full path from the root directory of the volume to a container file.
[out] ReadPlanEntries
Pointer to a ULONG variable that receives the number of DEDUP_CONTAINER_EXTENT structures in the array that the ReadPlan parameter points to.
[out] ReadPlan
Pointer to a buffer that receives an array of DEDUP_CONTAINER_EXTENT structures.
Return value
This method can return standard HRESULT values, such as S_OK. It can also return converted system error codes using the HRESULT_FROM_WIN32 macro. Possible return values include the following.
Remarks
Given a list of container files that hold data for the restore target file, the application optionally generates a list of container store file extents in a sorted order that results in an efficient cross-container read plan. For a backup store located on tape, this would normally be in tape order.
In the case where a container is stored in multiple extents in the backup store—for example, as a result of an incremental backup sequence—the application may also return multiple container extents for each logical container file.
The application may return S_OK and NULL output parameters to skip the read plan optimizations. In this case, container read order will be chosen by Data Deduplication.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | None supported |
| Minimum supported server | Windows Server 2012 |
| Target Platform | Windows |
| Header | ddpbackup.h |