Seagate ST3146755SS Reporting control, Determining rate, Predictive failures, Thermal monitor

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Reporting control

Reporting is controlled by the MRIE bits in the Informational Exceptions Control mode page (1Ch). Subject to the reporting method, the firmware will issue to the host an 01-5Dxx sense code. 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.

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

Cheetah 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 68°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

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Cheetah T10 SAS Product Manual, Rev. A

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Contents Cheetah T10 SAS Page Contents Defect and error management InstallationSeagate Technology support services Interface requirementsList of Figures Cheetah T10 SAS Product Manual, Rev. a Scope Cheetah T10 SAS disc driveCheetah T10 SAS Product Manual, Rev. a Standards, compliance and reference documents StandardsElectromagnetic compatibility Electromagnetic susceptibilityCompliance Reference documents Cheetah T10 SAS Product Manual, Rev. a General description Standard features Media descriptionPerformance Factory-installed accessories ReliabilityFormatted capacities Programmable drive capacityOptions factory installed User-installed accessoriesPerformance characteristics Internal drive characteristicsAccess time Seek timeFormat command execution time minutes 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 maintenanceHot plugging the drive 4 S.M.A.R.TControlling S.M.A.R.T Performance impactReporting control Determining ratePredictive failures Thermal monitorTemperature Log Page 0Dh Primary TemperatureReference Temperature Parameter Code DescriptionState of the drive prior to testing Invoking DSTShort and extended tests Short test Function Code 001bProduct warranty AbortShipping Product repair and return informationCheetah T10 SAS Product Manual, Rev. a Physical/electrical specifications AC power requirementsDC power requirements ST3300555SS DC power requirementsST3146755SS DC power requirements ST373355SS DC power requirementsST3146755SS Gbit mode Amps ST373355SS Gbit mode AmpsGeneral DC power requirement notes Power sequencingConducted noise immunity Current profilesTypical ST3300555SS drive current profiles Typical ST3146755SS drive current profiles Typical ST373355SS drive current profiles Power dissipation ST3300555SS in 3 Gbit operationST3300555SS in 1.5 Gbit operation ST3146755SS in 3 Gbit operation ST3146755SS in 1.5 Gbit operationST373355SS in 3 Gbit operation ST373355SS in 1.5 Gbit operationTemperature a. Operating Environmental limitsRelative humidity Effective altitude sea level a. OperatingShock and vibration ShockPackage size Packaged/product weight Drop height Recommended mountingAir cleanliness Vibration a. Operating-normalCorrosive environment Mechanical specifications AcousticsDefect and error management Drive internal defects/errorsDrive error recovery procedures Write retry count LBA cumulative, msec SAS system errors Background Media ScanMedia Pre-Scan Deferred Auto-Reallocation Idle Read After WriteInstallation Drive orientationCooling Air flowDrive mounting GroundingCheetah T10 SAS Product Manual, Rev. a SAS features Interface requirementsDual port support Scsi commands supported Commands supported by Cheetah T10 SAS family drivesCommand name Command code Supported Commands supported by Cheetah T10 SAS family drives Commands supported by Cheetah T10 SAS family drives Commands supported by Cheetah T10 SAS family drives Mode Sense data Inquiry dataCheetah T10 SAS inquiry data Bytes Data hexPage ST3300555SS Mode Sense data Mode PagesST3146755SS Mode Sense data ST373355SS Mode Sense data Miscellaneous operating features and conditions Miscellaneous featuresSupported Feature or condition Miscellaneous statusSAS physical interface Datum B Physical characteristics Connector requirementsPin Signal name Signal type Electrical descriptionPin descriptions SAS pin descriptionsSignal characteristics PowerSAS transmitters and receivers Ready LED OutLED drive signal Differential signalsGeneral interface characteristics Eye masks Eye masks overviewReceive eye mask Jitter tolerance masksAbsolute amplitude Normalized time in UIPeak-to SinusoidalJitter Frequency in kHzTransmitter signal characteristics Signal characteristica Units GbpsReceiver signal characteristics Signal characteristic Units GbpsMaximum allowable jitter Gbps m, n Deterministic jitterqImpedance specifications Receiver jitter toleranceCompliant jitter test pattern Cjtpat Impedance requirements Sheet 1Transmitter characteristics Impedance requirements Sheet 2Electrical TxRx connections = -5,437dB Shows the zero-length test load Receiver characteristics Cheetah T10 SAS Product Manual, Rev. a Seagate Technology support services Warranty ServiceInternet MySeagate Spp.seagate.com Presales SupportData Recovery Services Authorized Service Centers Data Recovery ServicesFAX services-All Europe toll call Call center Presales and Technical Support Warranty ServiceToll-free support numbers Africa/Middle East support services Index NumericsPage SAS See also cooling Page Seagate Technology LLC

ST3300555SS, ST3146755SS, ST373355SS specifications

The Seagate ST373355SS, ST3146755SS, and ST3300555SS represent a range of high-performance hard drives designed for enterprise applications, particularly in server environments requiring reliability, speed, and high capacity.

The ST373355SS is a 73.5 GB SCSI hard drive operating at 15,000 RPM, which ensures rapid data access and superior performance, making it ideal for transactional applications and data-intensive tasks. With its 4 MB cache, the drive leverages fast read and write speeds, enhancing overall system responsiveness. The SCSI interface, operating at 80 MB/s, allows for high-speed data transfers, making it a suitable choice for demanding environments where quick access to information is critical. Its hot-swappable feature enables maintenance without shutting down the system, maximizing uptime and productivity.

The ST3146755SS, with a capacity of 146.8 GB, builds on the performance of its predecessor while introducing improvements in data handling and reliability. Operating at the same impressive 15,000 RPM, this model also features a 16 MB cache that greatly improves data throughput and access speed. The drive is designed to reduce latency, which is crucial for applications where timing is everything. It is equipped with advanced error recovery features and Seagate’s innovative PowerTrim technology, which improves power efficiency during read and write operations. The ST3146755SS also features a higher mean time between failures (MTBF), underscoring its reliability in high-demand environments.

Lastly, the ST3300555SS offers even greater capacity with 300 GB. This drive maintains the 15,000 RPM rotation speed and benefits from a 16 MB cache, providing a balance of speed and storage capacity. Its advanced SCSI interface supports not just speed but also data integrity, ensuring consistent performance during extensive data transfers. The drive is designed to handle workloads naturally associated with enterprise servers, data warehouses, and video editing applications. Its rugged build supports continuous operation and is tested for high-temperature environments to ensure durability.

In summary, the Seagate ST373355SS, ST3146755SS, and ST3300555SS hard drives are engineered for enterprise environments, combining impressive RPM speeds, significant storage capacities, and advanced technologies to deliver reliability, performance, and efficiency for critical applications. These hard drives represent Seagate's commitment to providing solutions that meet the rigorous demands of modern data environments.
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