Seagate ST3450056FC (FDE), ST3146756FC (FDE), ST3300056FC (FDE) manual Prefetch operation

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are to be written are already stored in the cache from a previous read or write command. If there are, the respective cache segments are cleared. The new data is cached for subsequent Read commands.

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 gen- erated.

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.

Table 21 shows the mode default settings for the drive.

4.5.2Prefetch operation

If the Prefetch feature is enabled, data in contiguous logical blocks on the disc immediately beyond that which was requested by a Read command are retrieved and stored in the buffer for immediate transfer from the buffer to the host on subsequent Read commands that request those logical blocks (this is true even if cache operation is disabled). Though the prefetch operation uses the buffer as a cache, finding the requested data in the buffer is a prefetch hit, not a cache operation hit.

To enable Prefetch, use Mode Select page 08h, byte 12, bit 5 (Disable Read Ahead - DRA bit). DRA bit = 0 enables prefetch.

The drive does not use the Max Prefetch field (bytes 8 and 9) or the Prefetch Ceiling field (bytes 10 and 11).

When prefetch (read look-ahead) is enabled (enabled by DRA = 0), the drive enables prefetch of contiguous blocks from the disc when it senses that a prefetch hit will likely occur. The drive disables prefetch when it decides that a prefetch hit is not likely to occur.

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Cheetah 15K.6 FC Product Manual, Rev. C

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Contents ST3146356FC ST3450856FCST3300656FC Page Contents Physical/electrical specifications Defect and error managementInstallation Interface requirementsSeagate Technology support services Cheetah 15K.6 FC Product Manual, Rev. C Scope Model Number Full Disk Encryption FDECheetah 15K.6 FC Product Manual, Rev. C Applicable standards and reference documentation StandardsElectromagnetic compatibility Electromagnetic susceptibilityEuropean Union Restriction of Hazardous Substances RoHS Reference documents Ncits TR-20Cheetah 15K.6 FC Product Manual, Rev. C General description Standard features Media description PerformanceReliability Formatted capacitiesFactory-installed options User-installed accessoriesPerformance characteristics Internal drive characteristicsSeek performance characteristics Access timeFormat command execution time minutes General performance characteristicsStart/stop time 176 144 100Caching write data Prefetch/multi-segmented cache controlCache operation Prefetch operation Reliability 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 MillisecondsTemperature Log Page 0Dh Determining ratePredictive failures Thermal monitorState 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 repair and return information Product warrantyShipping Cheetah 15K.6 FC Product Manual, Rev. C DC power requirements Physical/electrical specificationsAC power requirements ST3450856FC DC power requirements Gbit Amps ST3450056FC DC power requirements Gbit AmpsST3300656FC DC power requirements Gbit Amps ST3300056FC DC power requirements Gbit AmpsST3146356FC DC power requirements Gbit Amps ST3146756FC DC power requirements Gbit AmpsGeneral DC power requirement notes Power sequencingConducted noise immunity Current profilesTypical ST3450856FC current profiles Typical ST3450056FC current profiles Typical ST3300656FC current profiles Typical ST3300056FC current profiles Typical ST3146356FC current profiles Typical ST3146756FC current profiles Power dissipation 450GB models300GB models 146GB models TemperatureEnvironmental limits Relative humidity Effective altitude sea levelShock Package size Packaged/product weight Drop heightShock and vibration Recommended mounting Air cleanliness VibrationAcoustics Corrosive environmentRoHS compliance statement Mechanical specifications Mounting configuration dimensionsDrive error recovery procedures Defect and error managementDrive internal defects/errors Page FC-AL system errors Background Media ScanIdle Read After Write Media Pre-ScanDeferred Auto-Reallocation Installation Drive ID/option selectionDrive orientation CoolingDrive mounting GroundingPage Cheetah 15K.6 FC Product Manual, Rev. C FC-AL features Fibre Channel link service framesLink services supported Type of frame Interface requirementsFC Scsi FCP response codes Function name Response code Fibre Channel task management functionsFibre Channel task management responses Fibre Channel port login NPort login Plogi payload BytesFibre Channel port login accept Fibre Channel Process LoginNPort Login Accept ACC payload Bytes Process Login Plri payloadFibre Channel Process Login Accept Fibre Channel fabric loginProcess Login Accept ACC payload Bytes Fabric Login Flogi payload BytesFibre Channel fabric accept login Fabric Login Accept ACC payload BytesScsi commands supported Dual port supportFibre Channel Arbitrated Loop options FC-AL options supportedSupported commands Cheetah 15K.6 FC Product Manual, Rev. C Cheetah 15K.6 FC Product Manual, Rev. C Supported commands Cheetah 15K.6 FC inquiry data Bytes Data hex Mode Sense dataInquiry data Page Mode Data Header 000000 Cheetah 15K.6 FC Product Manual, Rev. C Miscellaneous operating features and conditions Miscellaneous featuresSupported Feature or condition Miscellaneous statusPhysical description Physical characteristicsFC-AL physical interface Pin descriptions Connector requirementsElectrical description FC-AL transmitters and receivers FC-SCA pin descriptions Pin Signal name Signal typePin Signal name Signal type Power Fault LED OutMotor start controls Enable port bypass signalsActive LED Out Parallel Enclosure Services Interface ESI 11 SEL6 through SEL0 ID linesHex Dec SettingArbitrated loop physical address Alpa values Device control codes Signal characteristicsTTL input characteristics FC Differential input LED driver signalsFC Differential output Receive eye diagram Eye diagram data values Link rate GHz Cheetah 15K.6 FC Product Manual, Rev. C Seagate Technology support services InternetPresales Support Technical SupportData Recovery Services Call CenterToll-freeDirect dialFAX Warranty ServiceData Recovery Services Authorized Service Centers Index NumericsFC-AL Flogi Plogi Page See also cooling

ST3450056FC (FDE), ST3146756FC (FDE), ST3300056FC (FDE) specifications

Seagate has established itself as a leader in data storage solutions, and among its high-performance offerings are the Seagate ST3300056FC (FDE), ST3146756FC (FDE), and ST3450056FC (FDE) drives. These drives are part of Seagate's enterprise-class, 3.5-inch form factor family, providing robust data security, reliability, and performance for demanding data center environments.

The ST3300056FC boasts a capacity of 3TB, making it ideal for applications that require substantial storage space. With a 7200 RPM spindle speed and a 6Gb/s Serial Attached SCSI (SAS) interface, this drive delivers rapid data access speeds and high throughput, catering to the needs of enterprise workflows and data-intensive applications. The FDE (Full Disk Encryption) feature ensures that all stored data is encrypted, providing an added layer of protection against unauthorized access, which is critical for businesses handling sensitive information.

Similarly, the ST3146756FC offers a 1.4TB capacity, also spinning at 7200 RPM and utilizing a 6Gb/s SAS interface. As with its counterpart, this drive incorporates FDE technology, making it an excellent choice for environments that prioritize data security while maintaining performance. The SAS interface enhances connectivity options and further improves reliability and data integrity, essential for mission-critical applications.

The ST3450056FC, with a capacity of 4.5TB, stands out as a powerful option for storage needs that exceed traditional offerings. With the same 7200 RPM spindle speed and 6Gb/s SAS interface, it ensures optimal performance across various workloads. The FDE functionality further enhances its appeal, making it suitable for organizations that must comply with stringent data protection regulations.

All three drives are built with Seagate's advanced technologies, including PowerBalance, which maximizes the spindle performance while optimizing power consumption and thermal management. They are also designed with vibration tolerance, enhancing their reliability in multi-drive systems and environments where space and airflow may be limited.

In summary, the Seagate ST3300056FC, ST3146756FC, and ST3450056FC drives exemplify cutting-edge engineering, catering to enterprise needs with their impressive capacities, robust performance, and built-in security. They are well-suited for organizations that prioritize reliability and data integrity, making them a vital component of modern storage infrastructures.
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