You can enable the copy threshold option (SOM 467) to help minimize the decline of host server I/O performance by lowering the workload on the storage system.
I/O performance of the host server might be lowered as the workload on the storage system increases. If you perform Thin Image restore operations when the workload on the storage system is high, I/O performance of the host server is more likely to be lowered because replication processes for the primary volumes are triggered. The copy threshold option (SOM 467) can be used to temporarily stop the replication processes triggered by the restore operations when the workload on the storage system is high. The copy threshold option (SOM 467) can contribute to minimizing the decline in I/O performance of the host server.
The copy threshold option (SOM 467) is applicable only when the workload on the storage system is excessively heavy. If the copy threshold option (SOM 467) is applied, all the replication processes triggered by restore operations are stopped.
Replication processes stopped by the copy threshold option (SOM 467) will be restarted as the workload on the storage system is lowered. Enabling the copy threshold option (SOM 467) stops replication processes for Thin Image and the following products when the storage system is overloaded.
- Thin Image Advanced
- ShadowImage
- ShadowImage for Mainframe
- Compatible FlashCopy® V2
- Volume Migration V2
For more information about enabling the copy threshold option (SOM 467), call customer support.
For more information about Compatible FlashCopy® V2, see the Hitachi Compatible FlashCopy/FlashCopy SE User Guide.