Seagate ST33000652SS manual Media Pre-Scan, Deferred Auto-Reallocation, Idle Read After Write

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With BMS, the host system can consume less power and system overhead by only checking BMS status and results rather than tying up the bus and consuming power in the process of host-initiated media scanning activity.

Since the background scan functions are only done during idle periods, BMS causes a negligible impact to system performance. The first BMS scan for a newly manufactured drive is performed as quickly as possible to verify the media and protect data by setting the “Start time after idle” to 5ms, all subsequent scans begin after 500ms of idle time. Other features that normally use idle time to function will function normally because BMS functions for bursts of 800ms and then suspends activity for 100ms to allow other background functions to operate.

BMS interrupts immediately to service host commands from the interface bus while performing reads. BMS will complete any BMS-initiated error recovery prior to returning to service host-initiated commands. Overhead associated with a return to host-servicing activity from BMS only impacts the first command that interrupted BMS, this results in a typical delay of about 1 ms.

10.5Media Pre-Scan

Media Pre-Scan is a feature that allows the drive to repair media errors that would otherwise have been found by the host system during critical data accesses early in the drive’s life. The default setting for Media Pre-Scan is enabled on standard products. Media Pre-Scan checks each write command to determine if the destination LBAs have been scanned by BMS. If the LBAs have been verified, the drive proceeds with the normal write command. If the LBAs have not been verified by BMS, Pre-Scan will convert the write to a write verify to certify that the data was properly written to the disk.

Note. During Pre-Scan write verify commands, write performance may decrease by 50% until Pre-Scan completes. Write performance testing should be performed after Pre-Scan is complete. This may be checked by reading the BMS status.

To expedite the scan of the full pack and subsequently exit from the Pre-Scan period, BMS will begin scanning immediately when the drive goes to idle during the Pre-Scan period. In the event that the drive is in a high transaction traffic environment and is unable to complete a BMS scan within 24 power on hours BMS will disable Pre-Scan to restore full performance to the system.

10.6Deferred Auto-Reallocation

Deferred Auto-Reallocation (DAR) simplifies reallocation algorithms at the system level by allowing the drive to reallocate unreadable locations on a subsequent write command. Sites are marked for DAR during read operations performed by the drive. When a write command is received for an LBA marked for DAR, the auto- reallocation process is invoked and attempts to rewrite the data to the original location. If a verification of this rewrite fails, the sector is re-mapped to a spare location.

This is in contrast to the system having to use the Reassign Command to reassign a location that was unreadable and then generate a write command to rewrite the data. DAR is most effective when AWRE and ARRE are enabled—this is the default setting from the Seagate factory. With AWRE and ARRE disabled DAR is unable to reallocate the failing location and will report an error sense code indicating that a write command is being attempted to a previously failing location.

10.7Idle Read After Write

Idle Read After Write (IRAW) utilizes idle time to verify the integrity of recently written data. During idle periods, no active system requests, the drive reads recently written data from the media and compares it to valid write command data resident in the drives data buffer. Any sectors that fail the comparison result in the invocation of a rewrite and auto-reallocation process. The process attempts to rewrite the data to the original location. If a verification of this rewrite fails, the sector is re-mapped to a spare location.

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Constellation ES.2 SAS Product Manual, Rev. D

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Contents ST33000650SSST33000651SS Standard Model Self-Encrypting Drive ModelSED Fips 140-2 Model Review Pending ST33000652SS Revision history Contents Defect and error management InstallationAbout Fips About self-encrypting drives Interface requirementsPage Constellation ES.2 SAS Product Manual, Rev. D List of Figures Constellation ES.2 SAS Product Manual, Rev. D Seagate Technology support services Seagate Online Support and ServicesScope Applicable standards and reference documentation StandardsElectromagnetic compatibility Electromagnetic susceptibilityElectromagnetic compliance Electromagnetic compliance for the European UnionAustralian C-Tick Korean KCCEuropean Union Restriction of Hazardous Substances RoHS Reference documents Self-Encrypting Drives Reference ManualGeneral description Standard features Media descriptionPerformance Factory-installed options ReliabilityFormatted capacities Programmable drive capacityPerformance characteristics Internal drive characteristicsSeek performance characteristics Access timeGeneral performance characteristics Start/stop timePrefetch/multi-segmented cache control Cache operationCaching write data Prefetch operationReliability specifications Error ratesRecoverable Errors Unrecoverable ErrorsReliability and service Seek errorsInterface errors Preventive maintenance4 S.M.A.R.T Controlling S.M.A.R.TPerformance impact Reporting controlTemperature Log Page 0Dh Parameter Code Description Predictive failuresThermal monitor State of the drive prior to testing Drive Self Test DSTDST failure definition ImplementationShort and extended tests Short test Function Code 001bExtended test Function Code 010b Log page entriesProduct warranty ShippingStorage Product repair and return informationPhysical/electrical specifications PowerChoiceTM power managementPowerChoice modes AC power requirements DC power requirementsPage General DC power requirement notes Power sequencingConducted noise immunity Current profiles TB model current profilesPower dissipation 3TB models in 3Gb operation3TB models in 6Gb operation Temperature a. Operating Environmental limitsRelative humidity Effective altitude sea level a. Operating Shock and vibrationShock Recommended mounting Air cleanliness Vibration a. Operating-normalAcoustics Corrosive environmentSee Section Constellation ES.2 SAS Product Manual, Rev. D Mechanical specifications Mounting configuration dimensionsAbout Fips PurposeLevel 2 security Controlled access Admin SPAbout self-encrypting drives Data encryptionDefault password Random number generator RNGDrive locking Data bandsAuthenticated firmware download Power requirementsSupported commands RevertSPDefect and error management Drive internal defects/errorsDrive error recovery procedures SAS system errors Background Media ScanMedia Pre-Scan Deferred Auto-ReallocationIdle Read After Write Setting and determining the current Type Level Protection Information PILevels of PI Identifying a Protection Information driveInstallation Drive orientationCooling Air flowDrive mounting GroundingSAS features Interface requirementsDual port support Scsi commands supported Supported commandsSupported commands Supported commands Supported commands Mode Sense data Inquiry dataConstellation ES.2 inquiry data Page Mode Sense data changeable and default values for 3TB drives Miscellaneous operating features and conditions Miscellaneous featuresMiscellaneous status SAS physical interface Datum B Section C C Section a a Physical characteristics Connector requirementsElectrical description Pin descriptionsSignal characteristics PowerSAS transmitters and receivers Ready LED OutSAS-2 Specification Compliance LED drive signalDifferential signals General interface characteristicsIndex NumericsKCC Msid Mtbf See also cooling Page Constellation ES.2 SAS Product Manual, Rev. D Page Seagate Technology LLC

ST33000652SS, ST33000650SS, ST33000651SS specifications

The Seagate ST33000651SS, ST33000650SS, and ST33000652SS are high-performance enterprise hard drives designed for demanding storage applications. These models are part of the Seagate Constellation ES series, known for their reliability and performance in server and data center environments.

One of the most notable features of these drives is their capacity. The ST33000651SS and ST33000650SS offer a storage capacity of 3TB, providing ample space for data-intensive applications. The ST33000652SS enhances this with a larger storage option, ensuring that organizations can meet growing data demands without needing frequent upgrades.

These drives utilize a SATA 6Gb/s interface, which allows for high-speed data transfer. This increased bandwidth is essential for applications that rely on rapid access, such as virtualization, cloud computing, and database management systems. Additionally, the drives support Native Command Queuing (NCQ), which enhances performance by optimizing the order in which read and write commands are executed.

Reliability is paramount in enterprise environments, and Seagate addresses this with several technologies designed to minimize downtime. The ST33000651SS and its counterparts feature a 7200 RPM spindle speed, which not only delivers fast access times but also contributes to the overall durability of the drives. They also come with advanced error correction and data integrity features, which safeguard against data loss.

Another important characteristic of these drives is their low power consumption. Operating at an average power usage of 6.0W, they help reduce operational costs, particularly in large-scale deployments. This energy efficiency is essential for organizations looking to maintain sustainability while maximizing performance.

In terms of physical design, these hard drives are built to endure tough conditions typically found in data centers. They come in a standard 3.5-inch form factor, ensuring compatibility with a wide range of servers and storage enclosures. The robust design further enhances their lifespan, making them a sound investment for enterprise storage solutions.

In summary, the Seagate ST33000651SS, ST33000650SS, and ST33000652SS hard drives offer a compelling combination of high capacity, fast data transfer rates, and reliability. Their advanced technologies and energy-efficient design make them ideal choices for enterprises that require dependable and high-performing storage solutions in their IT infrastructure.
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