Seagate ST973451SS, ST936751SS Predictive failures, Thermal monitor, Temperature Log Page 0Dh

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Error rate is the number of errors per operation. The algorithm that S.M.A.R.T. uses to record rates of error is to set thresholds for the number of errors and their interval. If the number of errors exceeds the threshold before the interval expires, the error rate is considered to be unacceptable. If the number of errors does not exceed the threshold before the interval expires, the error rate is considered to be acceptable. In either case, the inter- val and failure counters are reset and the process starts over.

Predictive failures

S.M.A.R.T. signals predictive failures when the drive is performing unacceptably for a period of time. The firm- ware keeps a running count of the number of times the error rate for each attribute is unacceptable. To accom- plish this, a counter is incremented each time the error rate is unacceptable and decremented (not to exceed zero) whenever the error rate is acceptable. If the counter continually increments such that it reaches the pre- dictive threshold, a predictive failure is signaled. This counter is referred to as the Failure History Counter. There is a separate Failure History Counter for each attribute.

5.2.5Thermal monitor

Savvio drives implement a temperature warning system which:

1.Signals the host if the temperature exceeds a value which would threaten the drive.

2.Signals the host if the temperature exceeds a user-specified value.

3.Saves a S.M.A.R.T. data frame on the drive which exceeds the threatening temperature value.

A temperature sensor monitors the drive temperature and issues a warning over the interface when the tem- perature exceeds a set threshold. The temperature is measured at power-up and then at ten-minute intervals after power-up.

The thermal monitor system generates a warning code of 01-0B01 when the temperature exceeds the speci- fied limit in compliance with the SCSI standard. The drive temperature is reported in the FRU code field of mode sense data. You can use this information to determine if the warning is due to the temperature exceeding the drive threatening temperature or the user-specified temperature.

This feature is controlled by the Enable Warning (EWasc) bit, and the reporting mechanism is controlled by the Method of Reporting Informational Exceptions field (MRIE) on the Informational Exceptions Control (IEC) mode page (1Ch).

The current algorithm implements two temperature trip points. The first trip point is set at 65°C which is the maximum temperature limit according to the drive specification. The second trip point is user-selectable using the Log Select command. The reference temperature parameter in the temperature log page (see Table 1) can be used to set this trip point. The default value for this drive is 65°C, however, you can set it to any value in the range of 0 to 65°C. If you specify a temperature greater than 65°C in this field, the temperature is rounded down to 65°C. A sense code is sent to the host to indicate the rounding of the parameter field.

Table 1:

Temperature Log Page (0Dh)

 

 

Parameter Code

Description

 

 

 

0000h

 

Primary Temperature

 

 

 

0001h

 

Reference Temperature

 

 

 

5.2.6Drive Self Test (DST)

Drive Self Test (DST) is a technology designed to recognize drive fault conditions that qualify the drive as a failed unit. DST validates the functionality of the drive at a system level.

There are two test coverage options implemented in DST:

1. Extended test

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Savvio 15K SAS Product Manual, Rev. B

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Contents Savvio 15K SAS 100407739 Rev. BPage Revision status summary sheet Savvio 15K SAS Product Manual, Rev. B Contents Seagate Technology support services Defect and error managementInstallation Interface requirementsList of Figures Page Scope Savvio 15K SAS Product Manual, Rev. B Electromagnetic compatibility Applicable standards and reference documentationStandards Electromagnetic susceptibilityAustralian C-Tick Electromagnetic complianceElectromagnetic compliance for the European Union Korean MICReference documents European Union Restriction of Hazardous Substances RoHSSavvio 15K SAS Product Manual, Rev. B General description Performance Standard featuresMedia description Formatted capacities Factory-installed accessoriesReliability Programmable drive capacityOptions Seek performance characteristics Performance characteristicsInternal drive characteristics Access time Gen 2.0 LP dataFormat command execution time General performance characteristicsCache operation Start/stop timePrefetch/multi-segmented cache control Caching write data Prefetch operationRecoverable Errors Reliability specificationsError rates Unrecoverable ErrorsInterface errors Reliability and serviceSeek errors Preventive maintenancePerformance impact 4 S.M.A.R.TControlling S.M.A.R.T Reporting controlThermal monitor Temperature Log Page 0DhPredictive failures Parameter Code DescriptionImplementation State of the drive prior to testingDST failure definition Invoking DSTExtended test Function Code 010b Product warrantyShort test Function Code 001b Log page entriesShipping Product repair and return informationSavvio 15K SAS Product Manual, Rev. B DC power requirements Physical/electrical specificationsAC power requirements ST973451SS DC power requirementsST936751SS DC power requirements General DC power requirement notesCurrent profiles Power sequencingConducted noise immunity Typical ST936751SS current profile ST973451SS in 1.5 Gbit operation Power dissipationST973451SS in 3 Gbit operation ST936751SS in 3 Gbit operation ST936751SS in 1.5 Gbit operationRelative humidity TemperatureEnvironmental limits Shock Effective altitude sea levelShock and vibration Recommended mounting Corrosive environment Air cleanlinessVibration Acoustics Mechanical specifications Mounting configuration dimensionsDrive error recovery procedures Defect and error managementDrive internal defects/errors SAS system errors Deferred Auto-Reallocation Background Media ScanMedia Pre-Scan Idle Read After Write Installation Drive orientationCooling Air flowDrive mounting GroundingSavvio 15K SAS Product Manual, Rev. B SAS features Interface requirementsDual port support Scsi commands supported Commands supported by Savvio SAS family driveCommands supported by Savvio SAS family drive Commands supported by Savvio SAS family drive Commands supported by Savvio SAS family drive Savvio inquiry data Mode Sense dataInquiry data Page Mode Data Header 04 45 dc cc 00 00 02 Miscellaneous status Miscellaneous operating features and conditionsMiscellaneous features SAS physical interface Datum B Section C C Section a a Electrical description Physical characteristicsConnector requirements Pin descriptionsSAS pin descriptions SAS transmitters and receiversSignal characteristics Receive eye mask General interface characteristicsEye masks Eye masks overview Jitter tolerance masks Z1 OPSinusoidal Transmitter signal characteristicsPeak-to JitterReceiver signal characteristics Compliant jitter test pattern Cjtpat Maximum allowable jitterReceiver jitter tolerance Impedance specifications Impedance requirements Sheet 1Electrical TxRx connections Transmitter characteristicsImpedance requirements Sheet 2 = -5,437dB Shows the zero-length test load Receiver characteristics Savvio 15K SAS Product Manual, Rev. B Presales Support Seagate Technology support servicesInternet Technical SupportData Recovery Services Call Center Toll-free Direct dial Warranty ServiceData Recovery Services Authorized Service Centers Index NumericsPage SAS See also cooling
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