HP StorageWorks XP Remote Web Console Software User Manual
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Figure 47 Async Option pane
All default settings indicate the current settings.
•
Pending Update Data Rate (%): XP Continuous Access Asynchronous sidefile threshold, which
is maximum amount of cache that can be used for storing XP Continuous Access Async
recordsets (sidefiles). Select any value between 30% and 70% (10% increments) (see
).
The current pending update data rate is common to both XP Continuous Access and TC390
operations. The most recently entered value is applied to all XP Continuous Access Async
operations.
If one or more consistency groups exist, this setting cannot be changed. This setting can only
be changed when no CT groups are assigned.
You can specify the Pending Update Data Rate from the Async Option pane of TC390. If the
specified Pending Update Data Rate is less than the I/O Delay Start or I/O Delay Increase
specified from the Async Option pane of XP Continuous Access, the Pending Update Data
Rate is available.
•
Offloading Timer (sec.): Amount of time (0-255 seconds) the MCU waits to send an XP
Continuous Access Async recordset to the RCU. The MCU suspends all affected XP Continuous
Access Async volume pairs if it cannot offload a recordset to the RCU within the specified time
(for example, the RCU is still responding channel-command-retry).
The offloading timer should be set to less than the HBA I/O timeout value.
When channel-extenders are used for XP Continuous Access Async, the offloading timer should
be set to 35 seconds or less to avoid affecting host I/O performance.
•
I/O Delay Start: Threshold (0-70%), which is maximum amount of cache for starting inflow
control for the asynchronous copy. When amount of cache used for async recordsets reaches
the specified threshold, the MCU controls the cache inflow.
•
I/O Delay Increase: Threshold (0-70%), which is maximum amount of cache for starting to
strengthen control over inflow for the asynchronous copy. When amount of cache used for
async recordsets reaches the specified threshold, the MCU controls cache inflow.
XP Continuous Access Asynchronous operations
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