Seagate ST400FM0103 ユーザーズマニュアル

Seagate 1200 SSD Product Manual, Rev. C

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OEMs may order the following items which are incorporated at the manufacturing facility during production or packaged 
before shipping. Some of the options available are (not an exhaustive list of possible options):
• Other capacities can be ordered depending on LBA size requested and other factors.
• Single-unit shipping pack. The drive is normally shipped in bulk packaging to provide maximum protection against transit 

damage. Units shipped individually require additional protection as provided by the single unit shipping pack. Users plan-
ning single unit distribution should specify this option.

• The Safety and Regulatory Agency Specifications, part number 75789512, is usually included with each standard OEM 

drive shipped, but extra copies may be ordered.

The drive is designed with a feature called Thin Provisioning.   Thin Provisioning is a technique which does not require 
Logical Blocks to be associated to Physical Blocks on the storage medium until such a time as needed.   The use of Thin 
Provisioning is a major factor in SSD products because it reduces the amount of wear leveling and garbage collection that 
must be performed.   The result is an increase in the products endurance. For more details on Logical Block Provisioning and 
Thin Provisioning, Reference the SBC-3 document provided by the T-10 committee.

The level of Thin Provisioning support may vary by product model. Devices that support Thin Provisioning are allowed to 
return a default data pattern for read requests made to Logical Blocks that have not been mapped to Physical Blocks by a 
previous WRITE command.

In order to determine if Thin Provisioning is supported and what features of it are implemented requires the system to send a 
READ CAPACITY 16 (9Eh) command to the drive. Thin Provisioning and the READ CAPACITY 16 (9Eh) command is 
defined in the Seagate SCSI Command Reference 100293068.

A logical block provisioning management enabled (LBPME) bit set to one indicates that the logical unit implements logical 

block provisioning management. An LBPME bit set to zero indicates that the logical unit is fully provisioned and does not 
implement logical block provisioning management.

A logical block provisioning read zeros (LBPRZ) bit set to one indicates that, for an unmapped LBA specified by a read 

operation, the device server sends user data with all bits set to zero to the data-in buffer. An LBPRZ bit set to zero indicates 
that, for an unmapped LBA specified by a read operation, the device server may send user data with all bits set to any value 
to the data-in buffer.

The UNMAP command requests that the device server break the association of a specific Logical Block address from a 
Physical Block, thereby freeing up the Physical Block from use and no longer requiring it to contain user data. An unmapped 
block will respond to a READ command with data that is determined by the setting of the LBPRZ bit in the READ CAPACITY 
parameter data.

A device which supports Thin Provisioning will be capable of performing a SCSI FORMAT UNIT command which allocates 

Logical Blocks Addresses that are not linked to Physical Block Locations. A FORMAT command will cause all LBAs to 
become unmapped.

The requirements in this section apply to any device which supports LBA unmapping.

Supported

Supported

Supported

Not Supported