Seagate ST200FX0002 4 S.M.A.R.T, Controlling S.M.A.R.T, Performance impact, Reporting control

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the static electricity from the drive carrier prior to inserting it into the system.

6.3.4S.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 administrators 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.

An application 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.

An application can interrogate the drive through the host to determine the time remaining before the next scheduled measurement and data logging process occurs. To accomplish this, issue a LOG SENSE command to log page 0x3E. This allows applications to control when S.M.A.R.T. interruptions occur. Forcing S.M.A.R.T. with the REZERO UNIT command resets the timer.

Performance impact

S.M.A.R.T. attribute data is saved to the media 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 media 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.

S.M.A.R.T. measures error rates. All errors for each monitored attribute are recorded. A counter keeps track of the number of errors for the current interval. This counter is referred to as the Failure Counter.

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Contents Standard Models Self-Encrypting Drive Models ST400FX0002ST400FX0012 ST200FX0002 ST100FX0002Revision history Contents Defect and error management Physical/electrical specificationsInstallation About self-encrypting drivesPage Pulsar XT.2 SAS Product Manual, Rev. B List of Figures Page Seagate Online Support and Services Seagate Technology support servicesScope Standards Applicable standards and reference documentationElectromagnetic compatibility Electromagnetic susceptibilityElectromagnetic compliance for the European Union Electromagnetic complianceAustralian C-Tick Korean KCCChina Restriction of Hazardous Substances RoHS Directive Reference documentsGeneral description Standard featuresPerformance Media descriptionReliability Formatted capacities Factory-installed optionsProgrammable drive capacity Thin Provisioning Drive Configuration Internal drive characteristics Performance characteristicsPerformance characteristics Access timePerformance Format Mode Dcrt Bit IP Bit 400GB 200GB 100GBCache control Start/stop timeCaching write data Error rates Reliability specificationsEndurance Management Preventive maintenance Reliability and serviceData Retention Lifetime Endurance Management4 S.M.A.R.T Maximum processing delay Fully-enabled delayControlling S.M.A.R.T Performance impactThermal monitor Predictive failuresDrive Self Test DST State of the drive prior to testingDST failure definition ImplementationShort test Function Code 001b Short and extended testsExtended test Function Code 010b Log page entriesShipping Product warrantyProduct repair and return information StoragePower specifications Physical/electrical specificationsAC power requirements 400GB standard model DC power requirements DC power requirements200GB standard model DC power requirements 100GB standard model DC power requirements Power sequencing General DC power requirement notesConducted noise immunity Current profilesCurrent profiles for 200GB models 400GB models in 6Gb operation Power dissipation200GB models in 6Gb operation Environmental limits Temperature a. Operating100GB models in 6Gb operation Effective altitude sea level a. Operating Relative humidityShock and vibration Recommended mounting ShockVibration a. Operating-normal Air cleanlinessCorrosive environment Mounting configuration dimensions 400GB models Mechanical specificationsWeight Pounds 100 grams Admin SP Controlled accessAbout self-encrypting drives Data encryptionRandom number generator RNG Default passwordDrive locking Data bandsPower requirements Authenticated firmware downloadSupported commands Cryptographic eraseDrive internal defects/errors Defect and error managementSSD Physical format address descriptor Bit Byte SAS system errors Drive error recovery proceduresBackground Media Scan Auto-ReallocationProtection Information PI Setting and determining the current Type LevelLevels of PI Identifying a Protection Information driveDrive orientation InstallationAir flow CoolingGrounding Drive mountingInterface requirements SAS featuresDual port support Supported commands Scsi commands supportedPersistent Reserve Read Capacity Write Inquiry data Mode Sense dataPage 14 1a 00 1a Mode Sense data for 400GB drivesMode Pages Mode Sense data for 200GB drivesMode Sense values for 100GB drives Miscellaneous features Miscellaneous operating features and conditionsMiscellaneous status SAS physical interfaceDatum B Section C C Section a a Connector requirements Physical characteristicsElectrical description Pin descriptionsPower Signal characteristicsSAS transmitters and receivers Ready LED OutLED drive signal SAS-2 Specification complianceDifferential signals General interface characteristicsNumerics IndexPage RNG See also cooling Page Americas Seagate Technology LLC
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