Seagate ST373355SS Hot plugging the drive, 4 S.M.A.R.T, Controlling S.M.A.R.T, Performance impact

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5.2.3Hot plugging the drive

When a disc is powered on by switching the power or hot plugged, the drive runs a self test before attempting to communicate on its’ interfaces. When the self test completes successfully, the drive initiates a Link Reset starting with OOB. An attached device should respond to the link reset. If the link reset attempt fails, or any time the drive looses sync, the drive initiated link reset. The drive will initiate link reset once per second but alternates between port A and B. Therefore each port will attempt a link reset once per 2 seconds assuming both ports are out of sync..

If the self-test fails, the does not respond to link reset on the failing port.

Note. It is the responsibility of the systems integrator to assure that no temperature, energy, voltage haz- ard, or ESD potential hazard is presented during the hot connect/disconnect operation. Discharge the static electricity from the drive carrier prior to inserting it into the system.

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 two hours.

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 two hours subject to an idle period on the drive interfaces. The process of measuring off-line attribute data and saving data to the disc is uninterruptable. The maximum on-line only processing delay is summarized below:

Maximum processing delay

 

 

On-line only delay

Fully-enabled delay

 

DEXCPT = 0, PERF = 1

DEXCPT = 0, PERF = 0

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

42 milliseconds

163 milliseconds

Cheetah T10 SAS Product Manual, Rev. A

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Contents Cheetah T10 SAS Page Contents Interface requirements Defect and error managementInstallation Seagate Technology support servicesList of Figures Cheetah T10 SAS Product Manual, Rev. a Cheetah T10 SAS disc drive ScopeCheetah T10 SAS Product Manual, Rev. a Electromagnetic susceptibility Standards, compliance and reference documentsStandards Electromagnetic compatibilityCompliance Reference documents Cheetah T10 SAS Product Manual, Rev. a General description Performance Standard featuresMedia description Programmable drive capacity Factory-installed accessoriesReliability Formatted capacitiesUser-installed accessories Options factory installedSeek time Performance characteristicsInternal drive characteristics Access timeStart/stop time Format command execution time minutesGeneral performance characteristics Cache operation Prefetch/multi-segmented cache controlPrefetch operation Caching write dataUnrecoverable Errors Reliability specificationsError rates Recoverable ErrorsPreventive maintenance Reliability and serviceSeek errors Interface errorsPerformance impact Hot plugging the drive4 S.M.A.R.T Controlling S.M.A.R.TThermal monitor Reporting controlDetermining rate Predictive failuresParameter Code Description Temperature Log Page 0DhPrimary Temperature Reference TemperatureShort test Function Code 001b State of the drive prior to testingInvoking DST Short and extended testsProduct repair and return information Product warrantyAbort ShippingCheetah T10 SAS Product Manual, Rev. a ST3300555SS DC power requirements Physical/electrical specificationsAC power requirements DC power requirementsST373355SS Gbit mode Amps ST3146755SS DC power requirementsST373355SS DC power requirements ST3146755SS Gbit mode AmpsCurrent profiles General DC power requirement notesPower sequencing Conducted noise immunityTypical ST3300555SS drive current profiles Typical ST3146755SS drive current profiles Typical ST373355SS drive current profiles ST3300555SS in 1.5 Gbit operation Power dissipationST3300555SS in 3 Gbit operation ST3146755SS in 1.5 Gbit operation ST3146755SS in 3 Gbit operationST373355SS in 1.5 Gbit operation ST373355SS in 3 Gbit operationEnvironmental limits Temperature a. OperatingShock Relative humidityEffective altitude sea level a. Operating Shock and vibrationRecommended mounting Package size Packaged/product weight Drop heightCorrosive environment Air cleanlinessVibration a. Operating-normal Acoustics Mechanical specificationsDrive error recovery procedures Defect and error managementDrive internal defects/errors Write retry count LBA cumulative, msec Media Pre-Scan SAS system errorsBackground Media Scan Idle Read After Write Deferred Auto-ReallocationDrive orientation InstallationAir flow CoolingGrounding Drive mountingCheetah T10 SAS Product Manual, Rev. a Interface requirements SAS featuresDual port support Command name Command code Supported Scsi commands supportedCommands supported by Cheetah T10 SAS family drives Commands supported by Cheetah T10 SAS family drives Commands supported by Cheetah T10 SAS family drives Commands supported by Cheetah T10 SAS family drives Bytes Data hex Mode Sense dataInquiry data Cheetah T10 SAS inquiry dataPage Mode Pages ST3300555SS Mode Sense dataST3146755SS Mode Sense data ST373355SS Mode Sense data Miscellaneous status Miscellaneous operating features and conditionsMiscellaneous features Supported Feature or conditionSAS physical interface Datum B Connector requirements Physical characteristicsSAS pin descriptions Pin Signal name Signal typeElectrical description Pin descriptionsReady LED Out Signal characteristicsPower SAS transmitters and receiversEye masks Eye masks overview LED drive signalDifferential signals General interface characteristicsNormalized time in UI Receive eye maskJitter tolerance masks Absolute amplitudeFrequency in kHz Peak-toSinusoidal JitterSignal characteristica Units Gbps Transmitter signal characteristicsGbps m, n Deterministic jitterq Receiver signal characteristicsSignal characteristic Units Gbps Maximum allowable jitterImpedance requirements Sheet 1 Impedance specificationsReceiver jitter tolerance Compliant jitter test pattern CjtpatElectrical TxRx connections Transmitter characteristicsImpedance requirements Sheet 2 = -5,437dB Shows the zero-length test load Receiver characteristics Cheetah T10 SAS Product Manual, Rev. a Presales Support Seagate Technology support servicesWarranty Service Internet MySeagate Spp.seagate.comData Recovery Services Data Recovery Services Authorized Service CentersToll-free support numbers FAX services-All Europe toll callCall center Presales and Technical Support Warranty Service Africa/Middle East support services Numerics IndexPage 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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