Collected monitoring information is discarded, Tier relocation is canceled, Buffer area of a tier – HP XP P9500 Storage User Manual
Page 87
Collected monitoring information is discarded
The monitor information statuses are valid (VAL), invalid (INV), and calculating (PND) (see
). The recent monitoring information that is in valid or calculating status is discarded
under any of the following conditions:
•
When a pool-VOL is added (in the case of an increasing the number of tiers) or deleted.
•
The Auto LUN operation is performed. Collection of the monitoring information is discarded
only for the corresponding volumes.
•
The Quick Restore operation of Business Copy is performed. Collection of the monitoring
information is discarded only for the corresponding volumes
•
The initial copy operation of Continuous Access Synchronous is performed. Collection of the
monitoring information is discarded only for the corresponding volume.
If collected monitoring information is discarded, you must collect the monitoring information again.
If using Auto execution mode, or if your use scripts while in Manual execution mode, monitoring
information is automatically collected again and relocation is performed. The collected monitoring
information is discarded only for the corresponding volume.
Tier relocation is canceled
While tier relocation is in progress, tier relocation may be canceled under any of the following
conditions. To allow relocation to continue successfully, take the necessary actions described in
the table.
Solution
When tier relocation is canceled
Recover from the problem and perform relocation.
1
Cache is blocked.
Recover from the problem and perform relocation.
1
An LDEV is blocked (pool-VOL, THP V-VOL)
Add pool-VOL and perform collection of monitoring
information and relocation.
1
The used capacity of the pool reaches up to the Depletion
threshold during relocation.
Collect monitoring information again.
1
Collected monitoring information is discarded (see
2
Because the tier relocation in the next cycle is started
automatically, an action for this problem is
unnecessary.
1
The execution mode is Auto and the relocation is not completed
within an execution cycle.
Perform the tier relocation again.
When the execution mode is switched from Auto to Manual,
or Manual to Auto.
Notes:
1.
If the execution mode is Auto, or if you use scripts in the Manual execution mode, monitoring information will be
collected automatically again, and relocation will be performed.
2.
If the monitoring information about the corresponding volume is discarded, the relocation of the volume is cancelled.
Buffer area of a tier
Smart Tiers uses buffer percentages to reserve pages for new page assignments and allow the tier
relocation process. Areas necessary for processing these operations are distributed corresponding
to settings used by Smart Tiers. The following describes how processing takes place to handle the
buffer percentages.
Reserved pages for relocation operation: A small percentage of pages are reserved per tier to
allow relocation to operate. These are the buffer spaces for tier relocation
New page assignment: The new pages are first assigned to the top tier*. Pages are then assigned
to the lower tier, leaving a buffer area (2% per tier by default) for tier relocation. When 98% of
capacity of all tiers is assigned, the remaining 2% of the buffer space is assigned from the upper
Smart Tiers
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