Configuration Restrictions On The Cascade Of Truecopy With Snapshot; Cascade Restrictions With Snapshot Data Pool; Cache Memory Reconfiguration Cautions - Hitachi AMS2100 User Manual

Configuration restrictions on the Cascade of TrueCopy with SnapShot

Cascade restrictions with SnapShot Data Pool

Cache memory reconfiguration cautions

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Hitachi AMS 2000 Family Copy-on-Write SnapShot User Guide
Figure 1-7 shows an example of a configuration in which restrictions
are placed on the cascade of TrueCopy with SnapShot.
•
P-VOL
TrueCopy
P-VOL
TrueCopy
V-VOL
S-VOL
P-VOL
Local array
P-VOL
P-VOL
TrueCopy
V-VOL
P-VOL
TrueCopy
V-VOL
Local array
Figure 1-7: Configuration restrictions on the Cascade of
Neither TrueCopy/Simple DR pair nor ShadowImage pair can be
created using a data pool.
When the firmware version of the array is 0897/A or more, the
following cautions for cache memory reconfiguration processing in
the installation, un-installation, or invalidation/validation operation
occur.
• I/O processing performance
The I/O performance, in case of the sequential write pattern,
deteriorates approximately 20% to 30% by releasing a part of the
user data area in the cache memory and performing the memory
SnapShot overview
S-VOL
Remote array
P-VOL
S-VOL
S-VOL
S-VOL
Local array
Remote array
TrueCopy with SnapShot
S-VOL
TrueCopy
P-VOL
TrueCopy
V-VOL
P-VOL
Remote array