Seagate ST200FX0002, ST100FX0002, ST400FX0012 Start/stop time, Cache control, Caching write data

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Due to the nature of Flash memory technologies there are many factors that can result in values different than those stated in this specification. Some discrepancies can be caused by bandwidth limitations in the host adapter, operating system, or driver limitations. It is not the intent of this manual to cover all possible causes of performance discrepancies.

When evaluating performance of SSD devices, it is recommended to measure performance of the device in a method that resembles the targeted application using real world data and workloads. Test time should also be adequately large to ensure that sustainable metrics and measures are obtained.

5.3Start/stop time

The drive accepts the commands listed in the SAS Interface Manual less than 3 seconds after DC power has been applied.

If the drive receives a NOTIFY (ENABLE SPINUP) primitive through either port and has not received a START STOP UNIT command with the START bit equal to 0, the drive becomes ready for normal operations within 13 seconds (excluding the error recovery procedure).

If the drive receives a START STOP UNIT command with the START bit equal to 0 before receiving a NOTIFY (ENABLE SPINUP) primitive, the drive waits for a START STOP UNIT command with the START bit equal to 1. After receiving a START STOP UNIT command with the START bit equal to 1, the drive waits for a NOTIFY (ENABLE SPINUP) primitive. After receiving a NOTIFY (ENABLE SPINUP) primitive through either port, the drive becomes ready for normal operations within 13 seconds (excluding the error recovery procedure).

If the drive receives a START STOP UNIT command with the START bit and IMMED bit equal to 1 and does not receive a NOTIFY (ENABLE SPINUP) primitive within 5 seconds, the drive fails the START STOP UNIT command.

The START STOP UNIT command may be used to command the drive to stop. Stop time is 3 seconds (maxi- mum) from removal of DC power. SCSI stop time is 3 seconds. There is no power control switch on the drive.

5.4Cache control

All default cache mode parameter values (Mode Page 08h) for standard OEM versions of this drive family are given in Table 17 and 18.

5.4.1Caching write data

Write caching is a write operation by the drive that makes use of a drive buffer storage area where the data to be written to the medium is stored while the drive performs the WRITE command.

If the number of write data logical blocks exceed the size of the segment being written into, when the end of the segment is reached, the data is written into the beginning of the same cache segment, overwriting the data that was written there at the beginning of the operation; however, the drive does not overwrite data that has not yet been written to the medium.

If write caching is enabled (WCE=1), then the drive may return Good status on a WRITE command after the data has been transferred into the cache, but before the data has been written to the medium. If an error occurs while writing the data to the medium, and Good status has already been returned, a deferred error will be generated.

Data that has not been written to the medium is protected by a back up power source which provides the ability of the data to be written to non-volatile medium in the event of an unexpected power loss.

The SYNCHRONIZE CACHE command may be used to force the drive to write all cached write data to the medium. Upon completion of a SYNCHRONIZE CACHE command, all data received from previous WRITE commands will have been written to the medium. Tables 16, 17 and 18 show the mode default settings for the drive.

Pulsar XT.2 SAS Product Manual, Rev. B

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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 featuresMedia description PerformanceReliability Factory-installed options Formatted capacitiesProgrammable drive capacity Thin Provisioning Drive Configuration Internal drive characteristics Performance characteristicsPerformance characteristics Access timePerformance Format Mode Dcrt Bit IP Bit 400GB 200GB 100GBStart/stop time Cache controlCaching 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 StoragePhysical/electrical specifications Power 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 Power dissipation 400GB models in 6Gb operation200GB models in 6Gb operation Temperature a. Operating Environmental limits100GB models in 6Gb operation Relative humidity Effective altitude sea level a. OperatingShock and vibration Recommended mounting ShockAir cleanliness Vibration a. Operating-normalCorrosive 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 eraseDefect and error management Drive internal defects/errorsSSD 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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