Dell 38XX, 34XX, 32XX, 36XX manual Setting Modification Priority

running Linux. Typically, you need to change the host type only when you are setting up the storage array. The only time you might need to use this parameter is if you need to change how the storage array behaves relative to the hosts.

Before you can define the default host type, you need to determine what host types are connected to the storage array. To return information about host types connected to the storage array, you can use the show storageArray command with the defaultHostType parameter or hostTypeTable parameter. This command returns a list of the host types with which the RAID controller modules can communicate; it does not return a list of the hosts. The following examples show how to use the defaultHostType parameter and the hostTypeTable parameter:

client>smcli 123.45.67.89 -c "show storageArray defaultHostType;"

client>smcli 123.45.67.89 -c "show storageArray hostTypeTable;"

The following example shows how to define a specific default host type:

client>smcli 123.45.67.89 -c "set storageArray defaultHostType=11;"

The value 11 is the host type index value from the host type table.

Setting Modification Priority

Modification priority defines how much processing time is allocated for virtual disk modification operations. Time allocated for virtual disk modification operations affects system performance. Increases in virtual disk modification priority can reduce read/write performance. Operations affected by modification priority include:

•Copyback

•Reconstruction

•Initialization

•Changing segment size

•Defragmentation of a disk group

•Adding free capacity to a disk group

•Changing the RAID level of a disk group

The lowest priority rate favors system performance, but the modification operation takes longer. The highest priority rate favors the modification operation, but the system performance might be degraded.

The set virtualDisk command enables you to define the modification priority for a virtual disk. The following syntax is the general form of the command:

set (allVirtualDisks virtualDisk [virtualDiskName] virtualDisks [virtualDiskName1

... virtualDiskNamen] virtualDisk <wwid> accessVirtualDisk) modificationPriority=(highest high medium low lowest)

The following example shows how to use this command to set the modification priority for virtual disks named Engineering 1 and Engineering 2:

client>smcli 123.45.67.89 -c "set virtualDisks [\"Engineering_1\" \"Engineering_2\"] modificationPriority=lowest;"

The modification rate is set to lowest so that system performance is not significantly reduced by modification operations.

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