Setting the rate at which data is copied between volumes on storage systems that run IBM Spectrum Virtualize

Set the synchronization rate to avoid performance problems on volumes on IBM® SAN Volume Controller, IBM Spectrum Virtualize for Public Cloud, IBM Spectrum Virtualize as Software Only, and IBM Storwize® storage systems, and on IBM FlashSystem® devices that run IBM Spectrum Virtualize.

The synchronization rate on storage systems that run IBM Spectrum Virtualize is the rate at which the volume copies synchronize again after synchronization is lost. IBM Spectrum Control can do tasks that significantly alter the structure of storage. For example, IBM Spectrum Control can add a mirrored volume copy, or migrate volumes from one pool to another by using the storage optimizer functions. When IBM Spectrum Control does these tasks, by default, the synchronization rate is set to 50%.

The synchronization rate can cause performance problems on all volumes on storage systems that run IBM Spectrum Virtualize. However, you can use the tpctool command to change the synchronization rate.

To verify the current synchronization rate, go the installation_dir\cli directory, then use the getdscfg command:

tpctool getdscfg -user admin_user_id -pwd admin_user_password -url localhost:9550 
-property OptAutoController.SyncRate -context DeviceServer

If the synchronization rate is set to the default value of 50%, the tpctool command shows the following information:

Property                   Context      Value
=============================================
OptAutoController.SyncRate DeviceServer 50

To set the value of the synchronization rate to 70%, use the setdscfg command:

tpctool setdscfg -user admin_user_id -pwd admin_user_password  -url localhost:9550 
-property OptAutoController.SyncRate -context DeviceServer 70

The new synchronization rate is used for all storage systems that run IBM Spectrum Virtualize that you add to IBM Spectrum Control. You cannot set this value independently for each resource.

To verify that the value of the synchronization rate is modified, use the getdscfg command again. If the synchronization rate is set to 70%, the tpctool command shows the following information:

Property                   Context      Value
=============================================
OptAutoController.SyncRate DeviceServer 70

After you modify the value of the synchronization rate, stop and restart the Device server.