AMCC 9650SE, 9550SX, 9500S, 9590SE manual Supported Stripe Sizes KB

Controller Object Commands

stripe=Stripe consists of the stripe size to be used. The following table illustrates the supported and applicable stripes on unit types and controller models. Stripe size units are in K (kilobytes). If no stripe size is specified, 64K is used by default, if applicable. If you need to change the stripe size after the unit is created, you can do so my migrating the unit.

Table 7: Supported Stripe Sizes (KB)

Model	R0	R1	R5	R6	R10	JBOD	Spare	R50	Single
7K/8K	64	N/A	64	N/S	64	N/A	N/A	N/S	N/S
	128				128
	256				256
	512				512
	1024				1024
9000a	16	N/A	16	N/S	16	N/A	N/A	16	N/A
	64		64		64			64
	256		256		256			256
9650SE	16	N/A	16		16	N/A	N/A	16	N/A
	64		64	64	64			64
	256		256		256			256

a. Models 9500S, 9550SX, and 9590SE

group=345678 indicates the number of disks per group for a RAID 50 type. (This attribute can only be used when type=raid50.) Recall that a RAID 50 is a multi-tier array. At the bottom-most layer, N number of disks per group are used to form the RAID 5 layer. These RAID 5 arrays are then integrated into a RAID 0. This attribute allows you to specify the number of disks in the RAID 5 level. Valid values are 3, 4, 5, 6, 7, and 8.

Note that a sufficient number of disks are required for a given pattern or disk group. For example, given 6 disks, specifying 3 will create two RAID 5 arrays. With 12 disks, specifying 3 will create four RAID 5 arrays under the RAID 0 level. With only 6 disks a grouping of 6 is not allowed, as you would basically be creating a RAID 5.

The default RAID 50 grouping varies, based on number of disks. For 6 and 9 disks, default grouping is 3. For 8 disks, the default grouping is 4. For 10 disks, the default grouping is 5, and for 12 disks, the disks can be grouped into groups of 3, 4, or 6 drives (the group of 4 drives is set by default as it provides the best of net capacity and performance). For 15 disks, the disks can be

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