HP Smart Storage Adstrator manual Changing the controller cache ratio

<target> modify reenable [forced]

Example command:

=> ctrl slot=3 ld 1 modify reenable forced

Changing the controller cache ratio

The controller cache ratio setting determines the amount of memory allocated to read and write operations. Different types of applications have different optimum settings. You can change the ratio only if the controller has a battery-backed cache (because only battery-backed cache can be used for write cache) and if there are logical drives configured on the controller.

Syntax:

<target> modify cr=#/#?

where <target> is a controller, and #/# is the cache ratio in the format read percentage/write percentage.

Example command:

=> ctrl slot=3 modify cr=25/75

Enabling or disabling the drive cache

On controllers and drives that support physical drive write cache, you can use this command to enable or disable the write cache for all drives on the controller.

CAUTION: Because physical drive write cache is not battery-backed, you could lose data if a power failure occurs during a write process. To minimize this possibility, use a backup power supply.

Syntax:

<target> modify drivewritecache=enabledisable? [forced]

where <target> is a controller that supports drive write cache.

Example command:

=> ctrl slot=5 modify dwc=enable

Enabling or disabling the array accelerator

If the controller has an array accelerator, you can disable or enable it for specified logical drives.

NOTE: Disabling the array accelerator for a logical drive reserves use of the accelerator cache for other logical drives on the array. This feature is useful if you want the other logical drives to have the maximum possible performance (for example, if the logical drives contain database information).

Syntax:

<target> modify aa=enabledisable?

where <target> is a logical drive.

Example command:

=> ctrl slot=3 ld 1 modify aa=enable

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