HP XP P9500 Storage - Manual (Page 118)

Pool usage over either threshold will cause a warning to be issued in the form of SIMs (Service
Information Messages) to Remote Web Console and SNMP (Simple Network Management Protocol)
traps to the open-systems host. For more information on SNMP traps and the SNMP Manager, see
the HP XP P9000 SNMP Agent User Guide. See
“Working with SIMs” (page 120) for more
information about SIMs.
The following figure illustrates a total pool capacity of 1 TB, Warning Threshold of 50%, and
Depletion Threshold of 80%. If the used capacity of the pool is larger than 50% (500 GB) of the
total pool capacity, a SIM is reported to Remote Web Console and an SNMP trap is reported to
the open-systems host. If the used capacity of the pool increases and exceeds the Depletion Threshold
(80%), a SIM and an SNMP trap are reported again.
Note that in this scenario, if the actual pool usage percentage is 50.1%, only 50% appears on
the Remote Web Console window because the capacity amount is truncated after the decimal
point. If the threshold is set to 50%, a SIM and an SNMP trap are reported even though the pool
usage percentage appearing on the screen does not indicate an exceeded threshold.
NOTE: The system threshold does not exist in Thin Provisioning Z.
Pool subscription limit
The value of using subscription limit is to manage the maximum amount of over-provisioning that
is acceptable for a pool. By managing the pool subscription limit, you can control the potential
demand for storing data that might exceed the pool capacity.
The subscription limit is the ratio (%) of the total THP V-VOL capacity that has been configured to
the total capacity of the pool. When the subscription limit is set, you cannot configure another THP
V-VOL if the new THP V-VOL capacity would cause the subscription limit to be exceeded.
For example, if the pool capacity is 100 GB and the subscription limit is 150%, you can configure
up to a total of 150 GB of capacity to the THP V-VOLs related to the pool.
The following figure depicts setting the subscription limit of pool capacity.
118 Configuring thin provisioning