Seagate ST9300605FC, ST9900805FC Idle Read After Write, Protection Information PI, Levels of PI

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8.7Idle Read After Write

Idle Read After Write (IRAW) utilizes idle time to verify the integrity of recently written data. During idle periods, no active system requests, the drive reads recently written data from the media and compares it to valid write command data resident in the drives data buffer. Any sectors that fail the comparison result in the invocation of a rewrite and auto-reallocation process. The process attempts to rewrite the data to the original location. If a verification of this rewrite fails, the sector is re-mapped to a spare location.

8.8Protection Information (PI)

Protection Information is intended as a standardized approach to system level LRC traditionally provided by systems using 520 byte formatted LBAs. Drives formatted with PI information provide the same, common LBA count (i.e. same capacity point) as non-PI formatted drives. Sequential performance of a PI drive will be reduced by approximately 1.56% due to the extra overhead of PI being transferred from the media that is not calculated as part of the data transferred to the host. To determine the full transfer rate of a PI drive, transfers should be calculated by adding the 8 extra bytes of PI to the transferred LBA length, i.e. 512 + 8 = 520. PI for- matted drives are physically formatted to 520 byte sectors that store 512 bytes of customer data with 8 bytes of Protection Information appended to it. The advantage of PI is that the Protection Information bits can be man- aged at the HBA and HBA driver level. Allowing a system that typically does not support 520 LBA formats to integrate this level of protection.

Protection Information is valid with any supported LBA size. 512 LBA size is used here as common example.

8.8.1Levels of PI

There are 4 types of Protection Information.

Type 0 - Describes a drive that is not formatted with PI information bytes. This allows for legacy support in non- PI systems.

Type 1 - Provides support of PI protection using 10 and 16 byte commands. The RDPROTECT and WRTPRO- TECT bits allow for checking control through the CDB. Eight bytes of Protection Information are transmitted at LBA boundaries across the interface if RDPROTECT and WRTPROTECT bits are nonzero values. Type 1 does not allow the use of 32 byte commands.

Type 2 - Provides checking control and additional expected fields within the 32 byte CDBs. Eight bytes of Pro- tection Information are transmitted at LBA boundaries across the interface if RDPROTECT and WRTPRO- TECT bits are nonzero values. Type 2 does allow the use of 10 and 16 byte commands with zero values in the RDPROTECT and WRTPROTECT fields. The drive will generate 8 bytes (e.g.0xFFFF) 8 bytes of Protection Information to be stored on the media, but the 8 bytes will not be transferred to the host during a read com- mand.

Type 3 - Seagate products do not support Type 3.

8.8.2Setting and determining the current Type Level

A drive is initialized to a type of PI by using the format command on a PI capable drive. Once a drive is format- ted to a PI Type, it may be queried by a Read Capacity (16) command to report the PI type which it is currently formatted to. PI Types cannot coexist on a single drive. A drive can only be formatted to a single PI Type. It can be changed at anytime to a new Type but requires a low level format which destroys all existing data on the drive. No other vehicle for changing the PI type is provided by the T10 SBC3 specification.

Type 1

PI format CDB command: 04

90 00 00 00 00,

Write Buffer: 00 A0 00 00

Type 2

PI format CDB command: 04

D0 00 00 00 00,

Write Buffer: 00 A0 00 00

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Contents ST9900805FC ST9600205FC ST9450405FC ST9300605FC Savvio 10K.5 FCRevision history Contents Installation Savvio 10K.5 FC Product Manual, Rev. D Iii Savvio 10K.5 FC Product Manual, Rev. D Seagate Online Support and Services Seagate Technology support servicesScope Electromagnetic susceptibility Applicable standards and reference documentationStandards Electromagnetic compatibilityEuropean Union Restriction of Hazardous Substances RoHS China Restriction of Hazardous Substances RoHS Directive Reference documentsGeneral description Media description Standard featuresPerformance ReliabilityFormatted capacities Programmable drive capacity Factory-installed optionsSeek performance Performance characteristicsInternal drive characteristics Access timePrefetch/multi-segmented cache control Format command execution time minutesGeneral performance characteristics Start/stop timeCache operation Prefetch operation Caching write dataUnrecoverable Errors Reliability specificationsError rates Recoverable ErrorsPreventive maintenance Reliability and serviceSeek errors Interface errors4 S.M.A.R.T Controlling S.M.A.R.TPerformance impact Thermal monitor Reporting controlDetermining rate Predictive failuresDST failure definition State of the drive prior to testingTemperature Log Page 0Dh Drive Self Test DSTExtended test Function Code 010b Invoking DSTShort and extended tests Short test Function Code 001bProduct warranty AbortStorage Physical/electrical specifications PowerChoiceTM power managementPowerChoice modes AC power requirements DC power requirements for ST9900805FC model 2Gb 4Gb Amps DC power requirementsDC power requirements for ST9600205FC model 2Gb 4Gb Amps DC power requirements for ST9450405FC model 2Gb 4Gb Amps DC power requirements for ST9300605FC model 2Gb 4Gb Amps General DC power requirement notes Power sequencingConducted noise immunity Current profiles Savvio 10K.5 FC Product Manual, Rev. D Savvio 10K.5 FC Product Manual, Rev. D Savvio 10K.5 FC Product Manual, Rev. D ST9900805FC Power dissipationST9600205FC ST9450405FC ST9300605FC Temperature a. Operating Environmental limitsRelative humidity Effective altitude sea level a. Operating Shock and vibrationShock Recommended mounting Air cleanliness Vibration a. Operating-normalAcoustics Corrosive environment Mounting configuration dimensions Mechanical specificationsDefect and error management Drive internal defects/errorsDrive error recovery procedures FC-AL system errors Background Media Scan Media Pre-ScanDeferred Auto-Reallocation Levels of PI Setting and determining the current Type LevelIdle Read After Write Protection Information PIIdentifying a Protection Information drive Cooling InstallationDrive ID/option selection Drive orientationAir flow Drive mountingGrounding Interface requirements FC-AL featuresFibre Channel link service frames Link services supported Type of frameFibre Channel task management functions Fibre Channel task management responsesFC Scsi FCP response codes Function name Response code NPort login Plogi payload Bytes Fibre Channel port loginProcess Login Plri payload Fibre Channel port login acceptFibre Channel Process Login NPort Login Accept ACC payload BytesFabric Login Flogi payload Bytes Fibre Channel Process Login AcceptFibre Channel fabric login Process Login Accept ACC payload BytesFabric Login Accept ACC payload Bytes Fibre Channel fabric accept loginOption Supported Dual port supportFibre Channel Arbitrated Loop options FC-AL options supportedSupported commands Command code Command name Scsi commands supportedVerify error recovery page 07h Savvio 10K.5 FC Product Manual, Rev. D Temperature page 0Dh Mode Sense data Inquiry dataSavvio 10K.5 FC inquiry data Bytes Data hex Page Mode Data Header 00 00 00 00 45 dd 2f b0 00 00 00 00 00 00 02 00 00 00 00 34 65 f8 70 00 00 00 00 00 00 02 00 00 00 00 22 ec b2 5c 00 00 00 00 00 00 02 Supported Feature or condition Miscellaneous operating features and conditionsPhysical characteristics FC-AL physical interfacePhysical description Connector requirements Electrical descriptionPin descriptions FC-AL transmitters and receivers FC-SCA pin descriptions Pin Signal name Signal typeFault LED Out PowerEnable port bypass signals Active LED OutMotor start controls 10.5.11 SEL6 through SEL0 ID lines Parallel Enclosure Services Interface ESIAlpa SEL ID Signal characteristics 10.6.1 TTL input characteristicsDevice control codes LED driver signals FC Differential outputFC Differential input Receive eye diagram Eye diagram data values Link rate GHz Savvio 10K.5 FC Product Manual, Rev. D Index Devctrlcode Flogi Plogi Page Page Page Savvio 10K.5 FC Product Manual, Rev. D
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