Seagate ST9600204SS 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.

6.2.4S.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 interruptible. 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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Savvio 10K.4 SAS Product Manual, Rev. E

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Contents ST9600204SSST9600104SS ST9450404SSST9450304SS ST9600004SS ST9450204SSStandard Models Self-Encrypting Drive Models SED Fips 140-2 ModelsRevision history Contents Defect and error management InstallationAbout Fips About self-encrypting drives Interface requirementsPage Savvio 10K.4 SAS Product Manual, Rev. E 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 KCCReference documents European Union Restriction of Hazardous Substances RoHSGeneral description Standard features Media descriptionPerformance ReliabilityFormatted capacities Programmable drive capacityFactory-installed options Performance characteristics Internal drive characteristicsSeek performance characteristics Access timeGeneral performance characteristics Start/stop timePrefetch/multi-segmented cache control Cache operationCaching write data Prefetch operation Reliability specifications Error ratesRecoverable Errors Unrecoverable ErrorsReliability and service Seek errorsInterface errors Preventive maintenance4 S.M.A.R.T Controlling S.M.A.R.TPerformance impact Reporting controlTemperature 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 Physical/electrical specifications PowerChoiceTM power managementPowerChoice modes AC power requirements DC power requirementsPage 450GB standard model DC power requirements 0Gb mode Amps General DC power requirement notes Power sequencingConducted noise immunity Current profiles Current profiles for 600GB modelsCurrent profiles for 450GB models Power dissipation GB models in 3Gb operation600GB models in 6Gb operation 450GB models in 3Gb operation Temperature a. Operating Environmental limits450GB models in 6Gb operation Relative humidity Effective altitude sea level a. OperatingShock and vibration Shock Recommended mounting Air cleanliness Vibration a. Operating-normalCorrosive environment Acoustics Mechanical specifications Mounting configuration dimensionsAbout Fips PurposeLevel 2 security Controlled access Admin SPAbout 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 Scan Media Pre-ScanDeferred Auto-Reallocation Setting and determining the current Type Level Idle Read After WriteProtection Information PI Levels of PIIdentifying a Protection Information drive Installation Drive orientationCooling Air flowDrive mounting GroundingSAS features Interface requirementsDual port support Scsi commands supported Supported commandsSupported commands Supported commands Supported commands Mode Sense data Inquiry dataSavvio inquiry data Page Mode Sense data for 600GB drives Mode PagesMode Sense values for 450GB drives 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 NumericsKCC Msid Mtbf See also cooling Page Savvio 10K.4 SAS Product Manual, Rev. E Page Seagate Technology LLC
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