Seagate ST3146707LW/LC, ST3300007LW/LC, ST373207LW/LC manual Background Media Scan, Media Pre-Scan

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7.4Background Media Scan

Background Media Scan (BGMS) is a self-initiated media scan. It performs sequential reads across the entire pack of the media while the drive is idle. In RAID arrays, BGMS allows hot spare drives to be scanned for defects prior to being put into service by the host system. On regualr duty drives, if the host system makes use of the BGMS Log Page, it can avoid placing data in suspect locations on the media. Unrecovered error sites found during BGMS will be logged and recovered error sites will be logged or reallocated per ARRE/AWRE settings.

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

Since the background scan functions are only done during idle periods, BGMS causes a negligible impact to system performance. Background media scan will begin after 500ms of idle time. Other features that normally use idle time to function will function normally because BGMS functions for bursts of 800ms and then sus- pends activity to allow other background functions to operate. Additionally, BGMS operates in segments of 400 block reads, checking for host commands upon completion of each of the block segments.

The BGMS function will complete any BGMS-initiated error recovery prior to returning to service host-initiated commands. Overhead associated with a return to host-servicing activity from BGMS only impacts the first com- mand that interrupted BGMS. This results in a typical delay of about 4 ms.

7.4.1Media Pre-Scan

Media Pre-Scan is an optional feature that allows the drive to handle unrecovered media errors that would oth- erwise have been found by the host system during critical data accesses early in the integration process at customer sites. This should reduce integration DPPM (defective parts per million) by identifying and repairing media errors that arose during shipping and handling. Media Pre-Scan replaces all host-initiated Write com- mands with Write-Verify commands when the drive is accessing areas of the media yet untouched by BGMS- initiated scanning activity.

The drive will attempt to run BGMS on the entire pack of the drive. This will result in increasingly large portion so fthe drive having been accesed, provided there is adequate idle time to allow BGMS to run. During the Pre- Scan period, all Write commands that are in un-BGMS-scanned areas are converted to Write-Verify com- mands. To expedite the scan of the full pack and the subsequenty exit from the Pre-Scan period, BGMS will begin immediately when the drive goes to idle during the Pre-Scan period, as opposed to waiting 500ms as is done under non-Pre-Scan conditions.

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Cheetah 10K.7 SCSI Product Manual, Rev. D

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Contents Cheetah 10K.7 Scsi Page Cheetah 10K.7 Scsi Page Revision status summary sheet Page Contents Seagate Technology support services Defect and error managementInstallation Interface requirementsList of Figures Viii Cheetah 10K.7 Scsi Product Manual, Rev. D Scope Cheetah 10K.7 Scsi family drive ST3300007LC shownCheetah 10K.7 Scsi Product Manual, Rev. D Electromagnetic compatibility Applicable standards and reference documentationStandards Electromagnetic susceptibilityElectromagnetic compliance European Union Restriction of Hazardous Substances RoHSReference documents Cheetah 10K.7 Scsi Product Manual, Rev. D General description Standard features Media characteristicsPerformance ReliabilityFormatted capacities Accessories user installed Factory installed accessoriesOptions factory installed Programmable drive capacityPerformance characteristics Internal drive characteristics transparent to userScsi performance characteristics visible to user Generalized performance characteristics Access timeFormat command execution time minutes Ultra320 ScsiStart/stop time Prefetch/multi-segmented cache controlCache operation Caching write data Prefetch operation Cheetah 10K.7 Scsi Product Manual, Rev. D Recoverable Errors Reliability specificationsError rates Unrecoverable ErrorsPreventive maintenance Reliability and serviceSeek errors Annualized Failure Rate AFR4 S.M.A.R.T Controlling S.M.A.R.TDetermining rate Performance impactReporting control Predictive failuresParameter Code Description Drive Self Test DSTImplementation State of the drive prior to testingDST Failure Definition Invoking DSTExtended test Function Code 010b Product warrantyShort test Function Code 001b Log page entriesShipping Product repair and return informationPhysical/electrical specifications AC power requirementsDC power requirements ST3146707 SE mode LVD mode Power sequencing Conducted noise immunity3 12 V Current profile Typical ST3300007 drive +12 V current profile Typical ST3146707 drive +12 V current profile Typical ST373207 drive +12 V current profile Power dissipation ST3300007ST3146707 ST373207 Relative humidity TemperatureEnvironmental limits Effective altitude sea levelShock and vibration ShockRecommended mounting Air cleanliness VibrationCorrosive environment Mechanical specifications AcousticsLW mounting configuration dimensions LC mounting configuration dimensions Defect and error management Drive error recovery proceduresDrive internal defects Page Scsi systems errors Background Media Scan Media Pre-ScanDrive ID/option select header InstallationConfigure drive options FormattingJ6 jumper header J5 jumper header on LW models only J2 option select header on LW models only Function description RESDrive orientation CoolingDrive mounting GroundingCheetah 10K.7 Scsi Product Manual, Rev. D Interface requirements General descriptionScsi interface messages supported Scsi interface commands supported Page Page Page Inquiry Vital Product data Mode Sense data Mode Sense 10 Byte Header Data 00 ae 00 10 00 00 00 08 11 17 73 30 00 00 02 00 ae 00 10 00 00 00 08 08 8b b9 98 00 00 02 Scsi bus conditions and miscellaneous features supported Condition/feature supported bySynchronous data transfer periods supported Synchronous data transferPhysical interface 2 REQ/ACK offsetDC cable and connector PCB Scsi interface physical description Cable requirements Mating connectorsScsi interface cable requirements LC ModelsMating connectors for LW model drives Mating connectors for LC model drivesRight-angle to Pcba connectors Scsi daisy chain interface cabling for LW drives Nonshielded 68-pin Scsi device connector used on LW drives Nonshielded 80-pin Scsi SCA-2 connector, used on LC drives GND +DBP1 Charge Active LED OUT 4 REQ +REQ Active LED OUT 4 LVD output characteristics Electrical descriptionMultimode-SE and LVD alternatives LVD input characteristics General cable characteristicsSingle-ended drivers/receivers Cables for low voltage differential drivers/receivers Terminator requirements Terminator power LW drivesLC drives Disc drive Scsi timing Disc drive Scsi timing Spindle status Command status LED status Drive activity LEDPresales Support Seagate Technology support servicesInternet MySeagate Reseller.seagate.com Technical SupportWarranty Service Data Recovery Services Authorized Service CentersData Recovery Services FAX services-All Europe toll call Call center Presales and Technical Support Warranty ServiceToll-free support numbers Asia/Pacific support services Publication feedback survey Cheetah 10K.7 Scsi Product Manual, Rev. D Symbols NumericsPage Page PCB Page Cheetah 10K.7 Scsi Product Manual, Rev. D

ST3300007LW/LC, ST373207LW/LC, ST3146707LW/LC specifications

Seagate's ST3146707LW/LC, ST373207LW/LC, and ST3300007LW/LC are part of the company's renowned line of hard disk drives (HDDs), specifically designed for enterprise and high-performance computing environments. With their reliability and performance, these drives have become popular choices for data centers and critical applications requiring extensive storage capabilities.

One of the standout features of these models is their capacity to handle large volumes of data. The ST3146707LW/LC has a capacity of 146GB, while the ST373207LW/LC offers 73GB, and the ST3300007LW/LC comes with a substantial 300GB. These capacities make them well-suited for applications that require not only high storage space but also rapid access to data.

In terms of performance, these drives utilize a 10,000 RPM spindle speed, which significantly enhances data access times and overall performance. The combination of fast rotational speeds with Seagate's advanced caching algorithms allows for swift data retrieval, making these drives ideal for environments where speed is crucial.

These HDDs also employ the SCSI (Small Computer System Interface) interface, which promises high data transfer rates and reliability in enterprise-level applications. The Ultra320 SCSI interface can support transfer rates up to 320 MB/s, ensuring that the drives can efficiently communicate with other system components.

Another key technology featured in these models is Seagate's Adaptive Error Correction technology, which enhances data integrity and reliability. This feature helps in the detection and correction of errors that can occur during data transfer, reducing the risk of data loss.

Performance consistency is critical in enterprise environments, and these drives are built to endure the demands of 24/7 operation. They are designed with robust mechanisms to withstand temperature fluctuations, shock, and vibrations commonly found in data center settings.

In summary, the Seagate ST3146707LW/LC, ST373207LW/LC, and ST3300007LW/LC hard drives exemplify advanced features and technologies tailored for enterprise storage solutions. With significant capacities, impressive spindle speeds, SCSI connectivity, and reliability-focused technologies, these drives remain a valuable asset for businesses relying on stable and high-performance data storage.
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