AMCC 9590SE-4ME manual Cx/ux set storsave=protectbalanceperform quiet, By default, qpolicy is off

Unit Object Commands

By default, qpolicy is off.

Example:

//localhost> /c0/u5 set qpolicy = on

Setting Command Queuing Policy for unit /c0/u5 to [on] ... Done.

/cx/ux set storsave=protectbalanceperform [quiet]

This command applies only to 9550SX and 9590SE model controllers.

This command sets the storsave policy to be either protect, balance, or perform when the unit write cache is enabled. The default setting is protect.

The storsave policy adjusts several factors that control the balance between protection and performance on a unit. There is a trade-off among the available settings. The following description about the settings should help you to decide which one is suitable to you and your application. You will find further discussion of this setting in the 3ware Serial ATA RAID Controller User Guide, under “About StorSave Profile Levels” on page 48.

protect provides the maximum data protection among the controller settings. When storsave is set to protect mode, it means:

•When the unit becomes degraded, the write cache will be disabled.

•Write journaling is enabled. All data flushing from controller cache will be flushed to media.

•Incoming FUA (Force Unit Access) host requests will be honored unless a BBU is installed and enabled, in which case, they will be ignored.

perform provides the maximum performance and least data protection of the three controller settings. When storsave is set to perform mode, it means:

•When the unit becomes degraded, the write cache will not be disabled.

•Write journaling is disabled. All data flushing from controller cache will be flushed to disk. If a BBU is present, this essentially disables the BBU for this unit.

•Incoming FUA (Force Unit Access) host requests will be honored.

If you set the storsave policy to perform, a confirmation message will warn you that there could be data loss in the event of a power failure.

quiet is used for non-interactive mode. No confirmation is given and the command is executed immediately. This is useful for scripting purposes.

balance provides more data protection than perform mode but less data protection than protect mode, and provides better performance than protect mode but less performance than perform mode. When storsave is set to the balance mode, it means:

•When the unit becomes degraded, the write cache will not be disabled.

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