Seagate ST9450404SS 4 S.M.A.R.T, Controlling S.M.A.R.T, Performance impact, Reporting control

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Caution. The drive motor must come to a complete stop prior to changing the plane of operation. This time is required to insure data integrity.

5.2.4S.M.A.R.T.

S.M.A.R.T. is an acronym for Self-Monitoring Analysis and Reporting Technology. This technology is intended to recognize conditions that indicate imminent drive failure and is designed to provide sufficient warning of a failure to allow you to back up the data before an actual failure occurs.

Note. The drive’s firmware monitors specific attributes for degradation over time but can’t predict instanta- neous drive failures.

Each monitored attribute has been selected to monitor a specific set of failure conditions in the operating per- formance of the drive and the thresholds are optimized to minimize “false” and “failed” predictions.

Controlling S.M.A.R.T.

The operating mode of S.M.A.R.T. is controlled by the DEXCPT and PERF bits on the Informational Exceptions Control mode page (1Ch). Use the DEXCPT bit to enable or disable the S.M.A.R.T. feature. Setting the DEX- CPT bit disables all S.M.A.R.T. functions. When enabled, S.M.A.R.T. collects on-line data as the drive performs normal read and write operations. When the PERF bit is set, the drive is considered to be in “On-line Mode Only” and will not perform off-line functions.

You can measure off-line attributes and force the drive to save the data by using the Rezero Unit command. Forcing S.M.A.R.T. resets the timer so that the next scheduled interrupt is in one hour.

You can interrogate the drive through the host to determine the time remaining before the next scheduled mea- surement and data logging process occurs. To accomplish this, issue a Log Sense command to log page 0x3E. This allows you to control when S.M.A.R.T. interruptions occur. Forcing S.M.A.R.T. with the RTZ command resets the timer.

Performance impact

S.M.A.R.T. attribute data is saved to the disc so that the events that caused a predictive failure can be recre- ated. The drive measures and saves parameters once every hour subject to an idle period on the drive inter- faces. The process of measuring off-line attribute data and saving data to the disc is interruptable. The maximum on-line only processing delay is summarized below

Maximum processing delay

Fully-enabled delay

DEXCPT = 0

S.M.A.R.T. delay times 75 ms

Reporting control

Reporting is controlled by the MRIE bits in the Informational Exceptions Control mode page (1Ch). Subject to the reporting method. For example, if the MRIE is set to one, the firmware will issue to the host an 01-5D00 sense code. The FRU field contains the type of predictive failure that occurred. The error code is preserved through bus resets and power cycles.

Determining rate

S.M.A.R.T. monitors the rate at which errors occur and signals a predictive failure if the rate of degraded errors increases to an unacceptable level. To determine rate, error events are logged and compared to the number of total operations for a given attribute. The interval defines the number of operations over which to measure the rate. The counter that keeps track of the current number of operations is referred to as the Interval Counter.

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Contents Standard Models Self-Encrypting Drive Models ST9600204SSST9600104SS ST9450404SSST9450304SSRev. a 12/15/09 Initial release Revision historyContents Interface requirements Defect and error managementInstallation About self-encrypting drivesSeagate Technology support services Savvio 10K.4 SAS Product Manual, Rev. a List of Figures Page Scope Electromagnetic susceptibility Applicable standards and reference documentationStandards Electromagnetic compatibilityKorean KCC Electromagnetic complianceElectromagnetic compliance for the European Union Australian C-TickEuropean Union Restriction of Hazardous Substances RoHS Reference documentsGeneral description Media description Standard featuresProgrammable drive capacity PerformanceReliability Formatted capacitiesFactory-installed options Access time Performance characteristicsInternal drive characteristics Seek performance characteristicsStart/stop time General performance characteristicsCaching write data Prefetch/multi-segmented cache controlCache operation Prefetch operation Unrecoverable Errors Reliability specificationsError rates Recoverable ErrorsPreventive maintenance Reliability and serviceSeek errors Interface errorsPerformance impact Maximum processing delay Fully-enabled delay4 S.M.A.R.T Controlling S.M.A.R.TThermal monitor Temperature Log Page 0Dh Parameter Code DescriptionPredictive failures Implementation State of the drive prior to testingDrive Self Test DST DST failure definitionLog page entries Short and extended testsShort test Function Code 001b Extended test Function Code 010bProduct repair and return information Product warrantyShipping PowerChoice modes Physical/electrical specificationsPowerChoiceTM power management DC power requirements AC power requirementsSavvio 10K.4 SAS Product Manual, Rev. a Page Page Conducted noise immunity General DC power requirement notesPower sequencing Current profiles for 600GB models Current profilesCurrent profiles for 450GB models GB models in 3Gb operation Power dissipation600GB models in 6Gb operation 450GB models in 3Gb operation 450GB models in 6Gb operation Temperature a. OperatingEnvironmental limits Shock and vibration Relative humidityEffective altitude sea level a. Operating Shock Recommended mounting Corrosive environment Air cleanlinessVibration a. Operating-normal Acoustics Mounting configuration dimensions Mechanical specificationsData encryption Controlled accessAdmin SP About self-encrypting drivesData bands Default passwordRandom number generator RNG Drive lockingCryptographic erase Authenticated firmware downloadPower requirements Supported commandsDrive 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 Drive orientation InstallationAir flow CoolingGrounding Drive mountingInterface requirements SAS featuresDual port support Supported commands Scsi commands supportedSupported commands Supported commands Supported commands Savvio inquiry data Mode Sense dataInquiry data Page Mode Pages Mode Sense data for ST9600204SS and ST9600104SS drivesMode Sense values for ST9450404SS and ST9450304SS drives Miscellaneous status Miscellaneous operating features and conditionsMiscellaneous features SAS physical interface Datum B Section C C Section a a Pin descriptions Physical characteristicsConnector requirements Electrical descriptionReady LED Out Signal characteristicsPower SAS transmitters and receiversGeneral interface characteristics SAS-2 Specification complianceLED drive signal Differential signalsTechnical Support Seagate Technology support servicesInternet Presales SupportData Recovery Services Call Center Toll-free Direct dialFAX Warranty ServiceData Recovery Services Authorized Service Centers Numerics IndexKCC Msid Mtbf See also cooling Page Savvio 10K.4 SAS Product Manual, Rev. a Page Seagate Technology LLC
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