Compaq Infortrend manual Caching Operation, 128

Host LUN Geometry	1. Capacity <64GB: Head=63, Sector=32, Cylinder=?
User Configurable Default		(depends on capacity)
Geometry:	2.	64GB<capacity<128GB:Head=64, Sector=64,
		Cylinder=? (depends on capacity)
	3.	128GB<capacity<256GB: Head=127, Sector=64,
		Cylinder=? (depends on capacity)
	4.	256GB<capacity<512GB: Head=127, Sector=127,
		Cylinder=?
	5.	512GB<capacity<1TB: Head=255, Sector=64,
		Cylinder=? (depends on capacity)
	6. 1TB<capacity: Head=225, Sector=225, Cylinder=?
		(depends on capacity)
User Configurable	Sector: 32, 64, 127, 255 or Variable
Geometry range:	Head: 64, 127, 255 or Variable
	Cylinder: <1024, <32784,<65536 or Variable
Drive Motor Spin-up	Supported. The controller will send spin-up (start unit)
	command to each drive at the 4 sec. intervals.
Drive-side Tag Command	Supported. User adjustable up to 128 for each drive
Queue
Host-side Maximum	User adjustable up to 1024
Queued I/O count
Maximum concurrent Host	User adjustable up to 64
LUN connection
Number of Tags Reserved	User adjustable up to 256
for each Host-LUN
connection
Controller/Logical Drive	Turns controller or specific logical drive into a state that
Shutdown	does not receive I/Os. This function is available
	through OEM “iappend” program.
Drive I/O timeout	User adjustable
IO channel diagnostics	Supported
Drive Roaming	Supported

Caching Operation:

	Write-back Cache	Supported.
	Write-through Cache	Supported.
	Supported Memory type	SDRAM memory for enhanced performance
		Fast Page Memory with Parity for enhanced data
		security
	Read-ahead Operation	Intelligent Dynamic read-ahead operation for
		sequential data accessing
	Multi-Threaded Operation	Yes
	Scatter / Gather	Supported
	I/O sorting	Supported. Optimized I/O sorting for enhanced
		performance
	Variable Stripe Size		Opt. for Sequential	Opt. for
			I/O	Random I/O
		RAID0	128	32
Firmware	Functionality Specifications			B-3