Wide Striping; Figure 34 Wide Striping - Fujitsu ETERNUS DX S5 Series Design Manual

2. Basic Functions
Optimization of Volume Configurations
LUN Concatenation may not be available when other functions are being used in the ETERNUS DX or the target
volume.
For details on the functions that can be executed simultaneously, refer to
Available for Simultaneous Executions" (page
Caution
• It is recommended that the data on the volumes that are to be concatenated be backed up first.
• Refer to the applicable OS and file system documentation before dynamically expanding the volume
capacity because expanded volumes may not be recognized by some types and versions of server-side
platforms (OSs).
• When a volume that is using ETERNUS SF AdvancedCopy Manager to run backups is expanded via LUN
Concatenation, the volume will need to be registered with ETERNUS SF AdvancedCopy Manager again.
• When specifying a volume in the RAID group configured with Advanced Format drives as a
concatenation source or a concatenation destination to expand the capacity, the write performance may
be reduced when accessing the expanded volumes from an OS or an application that does not support
Advanced Format.

Wide Striping

Wide Striping is a function that concatenates multiple RAID groups by striping and uses many drives
simultaneously to improve performance. This function is effective when high random write performance is
required.
I/O accesses from the server are distributed to multiple drives by increasing the number of drives that configure
a LUN, which improves the processing performance.
Figure 34 Wide Striping
CM#0
Wide Striping creates a WSV that can be concatenated across 2 to 64 RAID groups.
The number of RAID groups that are to be concatenated is defined when creating a WSV. To change the number
of concatenated groups or expand the capacity of RAID groups after a WSV is created, perform RAID Migration.
Volumes can be concatenated up to 128TB.
Other volumes (Standard volumes, SDVs, SDPVs, or WSVs) can be created in the free area of a RAID group that is
concatenated by Wide Striping.
Server
CM#1
ETERNUS DX
325).
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"Combinations of Functions That Are
Design Guide