Seagate ST3400755SS Performance characteristics, Internal drive characteristics, Seek performance

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4.0Performance characteristics

This section provides detailed information concerning performance-related characteristics and features of Cheetah NS SAS drives.

4.1Internal drive characteristics

	ST3400755SS	Gbytes (formatted, rounded off value)*
Drive capacity	400.0	Gbytes (formatted, rounded off value)*
Read/write data heads	8
Tracks per surface (total)	92,200	Tracks (user accessible)
Tracks per inch	155,000	TPI
Peak bits per inch	979k	BPI
Areal Density	151.7	Gbits/inch2
Internal data rate	725 to 1,211	Mbits/sec (variable with zone)
Disk rotation speed	10k	rpm
Avg rotational latency	2.98	msec

*One Gbyte equals one billion bytes when referring to hard drive capacity. Accessible capacity may vary depending on operating environment and formatting.

4.2Seek performance

See Section 9.4.1, "SAS physical interface" on page 51 and the SAS Interface Manual (part number 100293071) for additional timing details.

4.2.1Access time

Not Including controller overhead1, 2 (msec)

		Read	Write
Average	Typical	3.9	4.2
Single track	Typical	0.35	0.52
Full stroke	Typical	6.8	7.5

1.Typical access times are measured under nominal conditions of temperature, voltage, and horizontal orientation as measured on a representative sample of drives.

2.Access to data = access time + latency time.

Cheetah NS SAS Product Manual, Rev. B

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Contents ST3400755SS Cheetah NS SASPage Contents Installation Defect and error managementSeagate Technology support services Interface requirementsTypical ST3400755SS drive +5V and +12V current profiles List of FiguresCheetah NS SAS Product Manual, Rev. B Scope Cheetah NS SAS Product Manual, Rev. B Standards Standards, compliance and reference documentsElectromagnetic compatibility Electromagnetic susceptibilityCompliance Reference documents Cheetah NS SAS Product Manual, Rev. B General description Media description Standard featuresPerformance ReliabilityFormatted capacities Factory-installed optionsProgrammable drive capacity ST3400755SSCheetah NS SAS Product Manual, Rev. B Internal drive characteristics Performance characteristicsAccess time Seek performanceStart/stop time Format command execution time minutesGeneral performance characteristics Caching write data Prefetch/multi-segmented cache controlCache operation Prefetch operation Error rates Reliability specificationsRecoverable Errors Unrecoverable ErrorsSeek errors Reliability and serviceInterface errors Preventive maintenanceControlling S.M.A.R.T 4 S.M.A.R.TPerformance impact Reporting controlThermal monitor Temperature Log Page 0DhPredictive failures DST failure definition State of the drive prior to testingImplementation Invoking DSTShort test Function Code 001b Product warrantyExtended test Function Code 010b Log page entriesProduct repair and return information ShippingCheetah NS SAS Product Manual, Rev. B AC power requirements Physical/electrical specificationsDC power requirements ST3400755SS DC power requirementsPower sequencing General DC power requirement notesConducted noise immunity Current profilesTypical ST3400755SS drive +5V and +12V current profiles Power dissipationEnvironmental limits TemperatureEffective altitude sea level Relative humidityShock and vibration ShockRecommended mounting Package size Packaged/product weight Drop heightVibration Air cleanlinessAcoustics Corrosive environmentChina Restriction of Hazardous Substances RoHS Directive X表示该部件（于同类物品程度上）所含的危险和有毒物质中国RoHS MCV标准所定义的门槛值。Physical dimensions Mechanical specificationsCheetah NS SAS Product Manual, Rev. B Drive error recovery procedures Defect and error managementDrive internal defects/errors 77.87 Media Pre-Scan SAS system errorsBackground Media Scan Idle Read After Write Deferred Auto-ReallocationDrive orientation InstallationAir flow CoolingGrounding Drive mountingCheetah NS SAS Product Manual, Rev. B Interface requirements SAS featuresDual port support Command name Command code Supported Scsi commands supportedCommands supported by Cheetah NS SAS family drives Commands supported by Cheetah NS SAS family drives Commands supported by Cheetah NS SAS family drives Commands supported by Cheetah NS SAS family drives Cheetah NS SAS inquiry data Bytes Data hex Mode Sense dataInquiry data Page Mode Pages 2.1 ST3400755SS Mode Sense dataMiscellaneous features Miscellaneous operating features and conditionsSupported Feature or condition Miscellaneous statusSAS physical interface Datum B Connector requirements Physical characteristicsElectrical description Pin Signal name Signal typePin descriptions SAS pin descriptionsPower Signal characteristicsSAS transmitters and receivers Ready LED OutDifferential signals LED drive signalGeneral interface characteristics Eye masks Eye masks overviewJitter tolerance masks Receive eye maskAbsolute amplitude Normalized time in UISinusoidal Peak-toJitter Frequency in kHzSignal characteristica Units Gbps Transmitter signal characteristicsSignal characteristic Units Gbps Receiver signal characteristicsMaximum allowable jitter Gbps m, n Deterministic jitterqReceiver jitter tolerance Impedance specificationsCompliant jitter test pattern Cjtpat Impedance requirements Sheet 1Electrical TxRx connections Transmitter characteristicsImpedance requirements Sheet 2 = -5,437dB Shows the zero-length test load Receiver characteristics Cheetah NS SAS Product Manual, Rev. B Internet Seagate Technology support servicesPresales Support Technical SupportData Recovery Services Call Center Toll-free Direct dial Warranty ServiceData Recovery Services Authorized Service Centers Numerics IndexPage SAS See also cooling