HP StorageWorks XP Remote Web Console Software User Manual
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Manual migration execution. XP Auto LUN will not execute a manual migration operation
when the current write pending rate for the storage system is 60% or higher.
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If heavy workloads are imposed on your storage system: Avoid volume migration operations
when heavy workloads are imposed on your storage system due to I/O requests from hosts.
If you perform a volume migration, the migration could fail. If the migration fails, reduce the
workloads on your storage system and then retry the volume migration.
Copy Threshold Option: If the load on a storage system increases, host server I/O performance
(response) may be degraded. If XP Auto LUN performs migration operations when the load
on a storage system is heavy, it is more likely that host server I/O performance (response)
may be degraded. The Copy Threshold option temporarily stops XP Auto LUN operations
when the load on a storage system is heavy. You can configure this option to minimize the
degradation of host I/O performance (response) by temporarily stopping XP Auto LUN
operations when the load on a storage system is heavy.
Migration of this volume is likely to fail when hosts frequently update volumes being migrated.
You can configure the Copy Threshold option to temporarily stop the copy processing of XP
Auto LUN when the load on a storage system is at capacity. HP does not recommend the use
of this option for hosts that frequently update volumes that are likely to be migrated because
of the increased possibility of failure during volume migration.
For information about setting the Copy Threshold option, call HP technical support (see
HP Technical Support” (page 76)
).
NOTE:
Copy operations that are stopped by the Copy Threshold option will resume when
the load on the storage system becomes light. If this option is turned on, not only will XP Auto
LUN operations stop if the load on the storage system becomes heavy, but the copy operations
of the following program products will also be interrupted:
◦
XP Business Copy
◦
ShadowImage for Mainframe
◦
FlashCopy Mirroring
◦
FlashCopy Mirroring V2
◦
XP Snapshot
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Progress Value: Even though an XP Auto LUN display may show that migration progress is
100% complete, it is possible that the migration is unfinished. This situation can occur when
a volume with heavy workloads (update I/Os between hosts and the storage system) are
migrated together with volumes with light workloads. In this situation, the migration of the
volumes may not have completed even though the progress value shows 100%. If this problem
occurs, execute either of the following to migrate the volumes:
◦
Reduce the workloads for update I/Os between hosts and the storage system and complete
the migration.
◦
Stop the volume migration for the volume with heavy workloads for update I/Os between
hosts and the storage system, execute a migration of another volume, and then retry the
migration that has been stopped.
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Effects on Other Program Products: When the workloads for update I/Os between hosts and
the storage system are heavy, more time will be required to complete the volume migration
because the copy of differential data is repeatedly executed. When differential data is being
copied, additional copying time may also be required for other program products.
shows the amount of additional copy time expected for affected program
Interoperability with Other Products
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