Seagate ST31000640SSIM Performance characteristics, Internal drive characteristics, Access time

Page 17

4.0Performance characteristics

This section provides detailed information concerning performance-related characteristics and features of Barracuda ES.2 SAS drives.

4.1Internal drive characteristics

	ST31000640SS	ST3750630SS	ST3500620SS
Drive capacity	1,000	750	500	Gbytes (formatted, rounded value)*
Read/write data heads	8	6	4
Tracks per inch	150,000	150,000	150,000	TPI
Peak bits per inch	1,090k	1,090k	1,090k	BPI
Areal Density	164	164	164	Gbits/inch2
Internal data rate	1,287	1,287	1,287	Mb/s max (variable with zone)
Sustained data rate	116	116	116	MB/s max (variable with zone)*
Disk rotation speed	7,200	7,200	7,200	RPM
Avg rotational latency	4.16	4.16	4.16	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 55 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	7.4	8.5
Single track	Typical	0.4	1.0
Full stroke	Typical	14.3	15.4

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.

Barracuda ES.2 SAS Product Manual, Rev. G

11

Image 17

Contents ST31000640SS ST3750630SS ST3500620SS Barracuda ES.2 SASPage Reliability specifications Performance characteristicsPhysical/electrical specifications General descriptionInterface requirements Defect and error managementInstallation Seagate Technology Support Services Barracuda ES.2 SAS Product Manual, Rev Scope Barracuda ES.2 SAS Product Manual, Rev. G Standards Standards, compliance and reference documentsElectromagnetic compatibility Electromagnetic susceptibilityCompliance Reference documents Barracuda ES.2 SAS Product Manual, Rev. G Barracuda ES.2 drive illustration General descriptionMedia description Standard featuresPerformance ReliabilityProgrammable drive capacity Factory-installed optionsFormatted capacities Barracuda ES.2 SAS Product Manual, Rev. G 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 ShippingBarracuda ES.2 SAS Product Manual, Rev. G AC power requirements Physical/electrical specificationsDC power requirements ST31000640SS DC power requirementsST3500620SS DC power requirements ST3750630SS DC power requirementsPower sequencing General DC power requirement notesConducted noise immunity Current profilesTypical ST31000640SS drive +5V and +12V current profiles Typical ST3500620SS drive +5V and +12V current profiles Power dissipationBarracuda ES.2 SAS Product Manual, Rev. G Environmental limits Temperature a. OperatingEffective altitude sea level a. Operating Relative humidityShock and vibration ShockPackage size Packaged/product weight Drop height Vibration a. Operating-normal Air cleanlinessAcoustics Corrosive environmentSee Section Barracuda ES.2 SAS Product Manual, Rev. G Physical dimensions Mechanical specificationsDrive error recovery procedures Defect and error managementDrive internal defects/errors 108.29 Media Pre-Scan SAS system errorsBackground Media Scan Idle Read After Write Deferred Auto-ReallocationDrive orientation InstallationAir flow CoolingGrounding Drive mountingBarracuda ES.2 SAS Product Manual, Rev. G Interface requirements SAS featuresDual port support Command name Command code Supported Scsi commands supportedCommands supported by Barracuda ES.2 SAS family drives Commands supported by Barracuda ES.2 SAS family drives Commands supported by Barracuda ES.2 SAS family drives Commands supported by Barracuda ES.2 SAS family drives Barracuda ES.2 SAS inquiry data Bytes Data hex Mode Sense dataInquiry data Page Mode Pages 2.1 ST31000640SS Mode Sense data2.2 ST3750630SS Mode Sense data 2.3 ST3500620SS Mode Sense data Miscellaneous 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 Barracuda ES.2 SAS Product Manual, Rev. G