Seagate ST9300653SS, ST9300553SS manual Defect and error management, Drive internal defects/errors

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10.0Defect and error management

Seagate continues to use innovative technologies to manage defects and errors. These technologies are designed to increase data integrity, perform drive self-maintenance, and validate proper drive operation.

SCSI defect and error management involves drive internal defect/error management and SAS system error considerations (errors in communications between the initiator and the drive). In addition, Seagate provides the following technologies used to increase data integrity and drive reliability:

•Background Media Scan (see Section 10.4)

•Media Pre-Scan (see Section 10.5)

•Deferred Auto-Reallocation (see Section 10.6)

•Idle Read After Write (see Section 10.7)

The read error rates and specified storage capacities are not dependent on host (initiator) defect management routines.

10.1Drive internal defects/errors

During the initial drive format operation at the factory, media defects are identified, tagged as being unusable, and their locations recorded on the drive primary defects list (referred to as the “P’ list and also as the ETF defect list). At factory format time, these known defects are also reallocated, that is, reassigned to a new place on the medium and the location listed in the defects reallocation table. The “P” list is not altered after factory formatting. Locations of defects found and reallocated during error recovery procedures after drive shipment are listed in the “G” list (defects growth list). The “P” and “G” lists may be referenced by the initiator using the Read Defect Data command.

Details of the SCSI commands supported by the drive are described in the SAS Interface Manual. Also, more information on the drive Error Recovery philosophy is presented in the SAS Interface Manual.

10.2Drive error recovery procedures

When an error occurs during drive operation, the drive, if programmed to do so, performs error recovery proce- dures to attempt to recover the data. The error recovery procedures used depend on the options previously set in the Error Recovery Parameters mode page. Error recovery and defect management may involve using sev- eral SCSI commands described in the SAS Interface Manual. The drive implements selectable error recovery time limits required in video applications.

The error recovery scheme supported by the drive provides a way to control the total error recovery time for the entire command in addition to controlling the recovery level for a single LBA. The total amount of time spent in error recovery for a command can be limited using the Recovery Time Limit bytes in the Error Recovery mode page. The total amount of time spent in error recovery for a single LBA can be limited using the Read Retry Count or Write Retry Count bytes in the Error Recovery mode page.

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Savvio 15K.3 SAS Product Manual, Rev. A

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Contents ST9300653SSST9300553SS ST9146853SSST9146753SS ST9300453SS ST9146653SSStandard Models Self-Encrypting Drive Models SED FIPS140-2 ModelsPage Contents Defect and error management InstallationAbout Fips About self-encrypting drives Interface requirementsPage Savvio 15K.3 SAS Product Manual, Rev. a List of Figures Page Seagate Technology support services Seagate Online Support and ServicesScope Applicable standards and reference documentation StandardsElectromagnetic compatibility Electromagnetic susceptibilityElectromagnetic compliance Electromagnetic compliance for the European UnionAustralian C-Tick Korean KCCEuropean Union Restriction of Hazardous Substances RoHS Scsi Commands Reference Manual SAS Interface Manual Reference documentsGeneral description Standard features Media descriptionPerformance ReliabilityFormatted capacities Factory installed options Programmable drive capacityPerformance characteristics Internal drive characteristicsSeek performance characteristics Access timeFormat command execution time General performance characteristicsStart/stop time Prefetch/multi-segmented cache control Cache operationCaching write data Prefetch operationReliability specifications Error ratesRecoverable Errors Unrecoverable ErrorsReliability and service Seek errorsInterface errors Preventive maintenanceMaximum processing delay 4 S.M.A.R.TControlling S.M.A.R.T Performance impactTemperature Log Page 0Dh Parameter Code Description Predictive failuresThermal monitor State of the drive prior to testing Drive Self Test DSTDST failure definition ImplementationShort and extended tests Short test Function Code 001bExtended test Function Code 010b Log page entriesProduct warranty ShippingProduct repair and return information StoragePhysical/electrical specifications PowerChoiceTM power managementPowerChoice modes AC power requirements DC power requirements300GB models DC power requirements Regulation146GB models DC power requirements General DC power requirement notes Power sequencingConducted noise immunity Current profiles Current profile for 300GB modelsCurrent profile for 146GB models Power dissipation 300GB models in 6Gb operation300GB models in 3Gb operation 146GB models in 6Gb operation 146GB models in 3Gb operationTemperature a. Operating Environmental limitsRelative humidity Effective altitude sea level a. Operating Shock and vibrationShock Vibration a. Operating-normal Recommended mountingAir cleanliness Corrosive environmentAcoustics Mechanical specifications DimensionsAbout Fips PurposeLevel 2 security Controlled access Admin SP About self-encrypting drives Data encryptionDefault password Random number generator RNGDrive locking Data bandsAuthenticated firmware download Power requirementsSupported commands Cryptographic eraseDefect and error management Drive internal defects/errorsDrive error recovery procedures SAS system errors Background Media ScanMedia Pre-Scan Deferred Auto-ReallocationIdle Read After Write Setting and determining the current Type Level Protection Information PILevels of PI Identifying a Protection Information driveInstallation Drive orientationCooling Air flowDrive mounting GroundingSAS features Interface requirementsScsi commands supported Supported commandsDual port support Supported commands Supported commands Supported commands Mode Sense data Inquiry dataSavvio inquiry data Page Mode Data Header Mode Data Header Miscellaneous operating features and conditions Miscellaneous featuresMiscellaneous status SAS physical interface Datum B Section C C Section a a Physical characteristics Connector requirementsElectrical description Pin descriptionsSignal characteristics PowerSAS transmitters and receivers Ready LED OutSAS-2 Specification compliance LED drive signalDifferential signals General interface characteristicsIndex NumericsPage Msid Mtbf See also cooling Page Savvio 15K.3 SAS Product Manual, Rev. a
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