服务器管理 > Snapshots for Historical Item Retrievals > Configuring Snapshot-based Historical Item Retrieval Mode
  
Configuring Snapshot-based Historical Item Retrieval Mode
The following steps are required to configure the snapshot mode for Workflows and Documents:
Generation of snapshots
Use of snapshots
Generation of snapshots
You can configure snapshot generation using the following policies:
mksis.im.snapshot.generation
This policy controls the generation of snapshots. The value of this policy is set to false by default. When the value is false, the system does not generate snapshot on item edits.
mksis.im.snapshot.generation.frequency
This policy controls the frequency at which the snapshots are generated in the system. This policy accepts a numeric value as an input. The value of this policy is set to 1000 by default, which means a snapshot is generated at every 1000th edit.
The snapshots are generated as and when a user edits an item. The system generates a snapshot after a specific number of edits where this number is controlled by the mksis.im.snapshot.generation.frequency policy. If this frequency changes, the next snapshot is generated after the number of edits match the new frequency value.
mksis.im.snapshot.generation.maxthreads
This policy controls the number of threads that are reserved for the snapshot generation process. The value of this policy is set to 3 by default.
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The snapshots are generated in the background thread and hence there is no performance impact on the edit operation.
Use of snapshots
You must set the value of mksis.im.snapshot property to true to use snapshots during historical item retrievals. This enables the use of snapshots for item retrieval in the system.
An Administrator can turn off the use of snapshots but enable snapshot generation so that even if the system is not using snapshots, it continues generating snapshots.
For details on the required properties, see the topic Workflow and Document Configuration Properties in the Database.