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: Wide Striping

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.

WSVs are created by concatenating RAID groups that have the same state with regard to the following conditions.

  • RAID level

  • Number of member drives

  • Stripe depth

  • Type of drive to be configured and rotational speed (for disks)

WSVs cannot be created in the following RAID groups.

  • RAID groups that belong to TPPs or FTRPs

  • RAID groups that are registered as REC Disk Buffers

  • RAID groups that are registered as Extreme Cache Pools

  • RAID groups that are configured with RAID6-FR

  • RAID groups without a continuous free area greater than the capacity of the volumes to be concatenated

Caution

  • Capacity expansion cannot be performed (LDE is not possible) for RAID groups used to configure a WSV.

  • If one or more RAID groups that are configured with Advanced Format drives are to be concatenated by striping to create a WSV, the write performance may be reduced when accessing the created WSVs from an OS or an application that does not support Advanced Format.