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FS System: Changing the QoS Priority of a LUN on R6 Does Not Trigger a QoS Migration (Doc ID 1990157.1)

Last updated on JANUARY 20, 2022

Applies to:

Oracle FS1-2 Flash Storage System - Version All Versions to All Versions [Release All Releases]
Information in this document applies to any platform.


This document explains the difference between R5 and R6 regarding the change of the Priority Level on an existing LUN and provides a workaround to users who would like to change the number of Drive Groups.  With Oracle FS System Manager with the R6 software, changing the Quality of Service (QoS) priority on a LUN does not trigger a QoS migration on R6 (QoS migration => restripe of a LUN to use more or less Drive Groups). The new priority is only reflected at the Controller level: Queue priority, more CPU, cache.  As such, changing the Priority Level of a LUN does not trigger a CmBackground task (visible by clicking on the Tasks button at the bottom right of the GUI) will only result in a ModifyLUN task.


Previously, with Axiom R5 systems, users may have been advised to change the QoS Priority to get more spindles in order to improve performance.  With the FS1-2 and R6, the spindle count can also be determined by the number and type of Drive Groups when a Storage Profile is used.  Custom Storage Profiles can also be created where the user can set the number of Drive Groups using the Stripe Width.

Conversely, uncheck the Use Storage Profile box and the number of Drive Groups will depend on the Priority Level used for the LUN:


PriorityNumber of Drive Groups
Archive / Low 2
Medium 3
High / Premium 4









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