Hitachi shadowimage for z/os software, Shadowimage for z/os software, Hitachi shadowimage™ for z/os software – HP StorageWorks XP Remote Web Console Software User Manual
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If Siz pairs that you want to perform copy operation are in the same parity group, reduce the
number of pairs at one copy operation. For example, if you want to split multiple Siz pairs in the
same parity group, wait until one pair is completely split before splitting another pair.
If the storage system is overloaded, you must increase cache, disk adapters, and/or RAID groups. It
is recommended that Siz T-VOLs are assigned in the newly installed RAID groups. If you continue Siz
operations with an overloaded storage system, host I/O performance may be degraded.
Copy Threshold Option
: If the load of storage system increases, host server I/O performance (response)
may be degraded. If Siz performs copy operations when the load of the storage system is heavy, it is
more likely that host server I/O performance (response) may be degraded. The Copy Threshold option
temporarily stops Siz copy operations when the load of the storage system is heavy. If you set this
option, you can minimize the degradation of host I/O performance by temporarily stopping Siz copy
operations when the load of the storage system is heavy.
Siz has another option called the Host I/O Performance option, which maintains host I/O performance
(response). Host I/O Performance option suppresses Siz copy operation regardless of the status of the
storage system. On the other hand, the Copy Threshold option is effective only when the load of the
storage system is heavy. When the Copy Threshold option is in effect, all the Siz copy operations stop.
For information about the setting of the Host I/O Performance option, see section
” on page 39. For information about the setting of the Copy Threshold
option, call HP technical support.
Copy operations that are stopped by the Copy Threshold option resume when the load of the storage
system becomes light. If you use this option, the Siz copy operation stops, as well as the following
program products when the load of the storage system is heavy:
•
XP Business Copy Software
•
XP for FlashCopy Mirroring Software
•
XP for FlashCopy Mirroring Software V2
•
XP Snapshot Software
•
Flex Copy XP Software
•
XP Auto LUN Software
Hitachi ShadowImage™ for z/OS Software
The Siz software on Remote Web Console displays Siz information and allows you to perform Siz
operations. The Siz runs on the web browser on the Remote Web Console computer and communicates
with the SVP of the connected storage system through the LAN. The Remote Web Console computer can
be attached to multiple Disk Arrays (XP1024/XP128/XP12000/XP10000/SVS 200). The Remote Web
Console computer acquires status from and issues commands to both the Siz S-VOLs and to the Siz T-VOLs.
If the Remote Web Console computer is not installed, contact your HP account team for information
on Siz configuration services.
Purchasing Volumes for Use with Hitachi ShadowImage™ for z/OS
When you purchase a license for volume capacity for use with Siz, you must determine how much volume
capacity you will need for any of the following:
•
Siz S-VOLs
•
Siz T-VOLs
•
Siz reserved volumes
•
FlashCopy S-VOLs
•
FlashCopy T-VOLs
The total capacity of volume that you can use cannot exceed the maximum volume capacity that is
licensed to you. You must therefore purchase a license for volume capacity that is equal to, or more
than, the total volume capacity you want to use.
Hitachi ShadowImage for z/OS user guide
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