Seagate ST200FX0002, ST100FX0002, ST400FX0012, ST400FX0002 manual Thin Provisioning

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4.8Thin Provisioning

4.8.1Logical Block Provisioning

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.

4.8.2Thin Provisioning capabilities

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.

Table 2: Thin Provisioning Product Configuration

Product Configuration

LBPME

LBPRZ

Non-SED

SED

Supported

Supported

Supported

Not Supported

 

 

A logical block provisioning management enabled (LBPME) bit set to one indicates that the logical unit imple- ments 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.

4.8.3UNMAP

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.

4.8.4FORMAT UNIT command

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 com- mand will cause all LBAs to become unmapped.

4.8.5Protection Information (PI) and Security (SED)

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

In SCSI devices, umapped LBAs are defined as part of the Thin Provisioning model. Support of the Thin Provi- sioning model is indicated by the LBPME bit having a value of '1' in the READ CAPACITY (16) parameter data.

Pulsar XT.2 SAS Product Manual, Rev. B

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Contents Standard Models Self-Encrypting Drive Models ST400FX0002ST400FX0012 ST200FX0002 ST100FX0002Revision history Contents Defect and error management Physical/electrical specificationsInstallation About self-encrypting drivesPage Pulsar XT.2 SAS Product Manual, Rev. B List of Figures Page Seagate Online Support and Services Seagate Technology support servicesScope Standards Applicable standards and reference documentationElectromagnetic compatibility Electromagnetic susceptibilityElectromagnetic compliance for the European Union Electromagnetic complianceAustralian C-Tick Korean KCCChina Restriction of Hazardous Substances RoHS Directive Reference documentsGeneral description Standard featuresReliability Media descriptionPerformance Programmable drive capacity Factory-installed optionsFormatted capacities Thin Provisioning Drive Configuration Internal drive characteristics Performance characteristicsPerformance characteristics Access timePerformance Format Mode Dcrt Bit IP Bit 400GB 200GB 100GBCaching write data Start/stop timeCache control Error rates Reliability specificationsEndurance Management Preventive maintenance Reliability and serviceData Retention Lifetime Endurance Management4 S.M.A.R.T Maximum processing delay Fully-enabled delayControlling S.M.A.R.T Performance impactThermal monitor Predictive failuresDrive Self Test DST State of the drive prior to testingDST failure definition ImplementationShort test Function Code 001b Short and extended testsExtended test Function Code 010b Log page entriesShipping Product warrantyProduct repair and return information StorageAC power requirements Physical/electrical specificationsPower specifications 400GB standard model DC power requirements DC power requirements200GB standard model DC power requirements 100GB standard model DC power requirements Power sequencing General DC power requirement notesConducted noise immunity Current profilesCurrent profiles for 200GB models 200GB models in 6Gb operation Power dissipation400GB models in 6Gb operation 100GB models in 6Gb operation Temperature a. OperatingEnvironmental limits Shock and vibration Relative humidityEffective altitude sea level a. Operating Recommended mounting ShockCorrosive environment Air cleanlinessVibration a. Operating-normal Mounting configuration dimensions 400GB models Mechanical specificationsWeight Pounds 100 grams Admin SP Controlled accessAbout self-encrypting drives Data encryptionRandom number generator RNG Default passwordDrive locking Data bandsPower requirements Authenticated firmware downloadSupported commands Cryptographic eraseSSD Physical format address descriptor Bit Byte Defect and error managementDrive internal defects/errors SAS system errors Drive error recovery proceduresBackground Media Scan Auto-ReallocationProtection Information PI Setting and determining the current Type LevelLevels of PI Identifying a Protection Information driveDrive orientation InstallationAir flow CoolingGrounding Drive mountingInterface requirements SAS featuresDual port support Supported commands Scsi commands supportedPersistent Reserve Read Capacity Write Inquiry data Mode Sense dataPage 14 1a 00 1a Mode Sense data for 400GB drivesMode Pages Mode Sense data for 200GB drivesMode Sense values for 100GB drives Miscellaneous features Miscellaneous operating features and conditionsMiscellaneous status SAS physical interfaceDatum B Section C C Section a a Connector requirements Physical characteristicsElectrical description Pin descriptionsPower Signal characteristicsSAS transmitters and receivers Ready LED OutLED drive signal SAS-2 Specification complianceDifferential signals General interface characteristicsNumerics IndexPage RNG See also cooling Page Americas Seagate Technology LLC
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