Seagate ST373355SS, ST3146755SS Maximum recovery time per, Write retry count LBA cumulative, msec

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The drive firmware error recovery algorithms consists of 11 levels for read recoveries and five levels for write. Each level may consist of multiple steps, where a step is defined as a recovery function involving a single re- read or re-write attempt. The maximum level used by the drive in LBA recovery is determined by the read and write retry counts.

Table 5 equates the read and write retry count with the maximum possible recovery time for read and write recovery of individual LBAs. The times given do not include time taken to perform reallocations. Reallocations are performed when the ARRE bit (for reads) or AWRE bit (for writes) is one, the RC bit is zero, and the recov- ery time limit for the command has not yet been met. Time needed to perform reallocation is not counted against the recovery time limit.

When the RC bit is one, reallocations are disabled even if the ARRE or AWRE bits are one. The drive will still perform data recovery actions within the limits defined by the Read Retry Count, Write Retry Count, and Recovery Time Limit parameters. However, the drive does not report any unrecovered errors.

Table 5: Read and write retry count maximum recovery times

Read retry count1

Maximum recovery time per

LBA (cumulative, msec)

 

 

0

51.87

 

 

1

59.85

 

 

2

203.49

 

 

3

219.45

 

 

4

253.11

 

 

5

279.35

 

 

6

311.27

 

 

7

395.12

 

 

8

463.12

 

 

9

495.04

 

 

10

530.95

 

 

11 (default)

1,282.97

 

 

1

Maximum recovery time per

Write retry count

LBA (cumulative, msec)

 

 

0

23.94

 

 

1

35.91

 

 

2

55.86

 

 

3

67.83

 

 

4

119.79

 

 

5 (default)

147.72

 

 

[1]These values are subject to change.

Setting these retry counts to a value below the default setting could result in degradation of the unrecov- ered error rate which may exceed the value given in this product manual. A setting of zero (0) will result in the drive not performing error recovery.

For example, suppose the read/write recovery page has the RC bit set to 0, read retry count set to 4, and the recovery time limit field (Mode Sense page 01, bytes 10 and 11) set to FF FF hex (maximum). A four LBA Read command is allowed to take up to 253.11 msec recovery time for each of the four LBAs in the command. If the recovery time limit is set to 00 C8 hex (200 msec decimal) a four LBA read command is allowed to take up to 200 msec for all error recovery within that command. The use of the Recovery Time Limit field allows finer granularity on control of the time spent in error recovery. The recovery time limit only starts counting when the drive is executing error recovery and it restarts on each command. There- fore, each command’s total recovery time is subject to the recovery time limit. Note: A recovery time limit of 0 will use the drive’s default value of FF FF. Minimum recovery time limit is achieved by setting the Recovery Time Limit field to 00 01.

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Cheetah T10 SAS Product Manual, Rev. A

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Contents Cheetah T10 SAS Page Contents Defect and error management InstallationSeagate Technology support services Interface requirementsList of Figures Cheetah T10 SAS Product Manual, Rev. a Scope Cheetah T10 SAS disc driveCheetah T10 SAS Product Manual, Rev. a Standards, compliance and reference documents StandardsElectromagnetic compatibility Electromagnetic susceptibilityCompliance Reference documents Cheetah T10 SAS Product Manual, Rev. a General description Performance Standard featuresMedia description Factory-installed accessories ReliabilityFormatted capacities Programmable drive capacityOptions factory installed User-installed accessoriesPerformance characteristics Internal drive characteristicsAccess time Seek timeStart/stop time Format command execution time minutesGeneral performance characteristics Prefetch/multi-segmented cache control Cache operationCaching write data Prefetch operationReliability specifications Error ratesRecoverable Errors Unrecoverable ErrorsReliability and service Seek errorsInterface errors Preventive maintenanceHot plugging the drive 4 S.M.A.R.TControlling S.M.A.R.T Performance impactReporting control Determining ratePredictive failures Thermal monitorTemperature Log Page 0Dh Primary TemperatureReference Temperature Parameter Code DescriptionState of the drive prior to testing Invoking DSTShort and extended tests Short test Function Code 001bProduct warranty AbortShipping Product repair and return informationCheetah T10 SAS Product Manual, Rev. a Physical/electrical specifications AC power requirementsDC power requirements ST3300555SS DC power requirementsST3146755SS DC power requirements ST373355SS DC power requirementsST3146755SS Gbit mode Amps ST373355SS Gbit mode AmpsGeneral DC power requirement notes Power sequencingConducted noise immunity Current profilesTypical ST3300555SS drive current profiles Typical ST3146755SS drive current profiles Typical ST373355SS drive current profiles ST3300555SS in 1.5 Gbit operation Power dissipationST3300555SS in 3 Gbit operation ST3146755SS in 3 Gbit operation ST3146755SS in 1.5 Gbit operationST373355SS in 3 Gbit operation ST373355SS in 1.5 Gbit operationTemperature a. Operating Environmental limitsRelative humidity Effective altitude sea level a. OperatingShock and vibration ShockPackage size Packaged/product weight Drop height Recommended mountingCorrosive environment Air cleanlinessVibration a. Operating-normal Mechanical specifications AcousticsDrive error recovery procedures Defect and error managementDrive internal defects/errors Write retry count LBA cumulative, msec Media Pre-Scan SAS system errorsBackground Media Scan Deferred Auto-Reallocation Idle Read After WriteInstallation Drive orientationCooling Air flowDrive mounting GroundingCheetah T10 SAS Product Manual, Rev. a SAS features Interface requirementsDual port support Command name Command code Supported Scsi commands supportedCommands supported by Cheetah T10 SAS family drives Commands supported by Cheetah T10 SAS family drives Commands supported by Cheetah T10 SAS family drives Commands supported by Cheetah T10 SAS family drives Mode Sense data Inquiry dataCheetah T10 SAS inquiry data Bytes Data hexPage ST3300555SS Mode Sense data Mode PagesST3146755SS Mode Sense data ST373355SS Mode Sense data Miscellaneous operating features and conditions Miscellaneous featuresSupported Feature or condition Miscellaneous statusSAS physical interface Datum B Physical characteristics Connector requirementsPin Signal name Signal type Electrical descriptionPin descriptions SAS pin descriptionsSignal characteristics PowerSAS transmitters and receivers Ready LED OutLED drive signal Differential signalsGeneral interface characteristics Eye masks Eye masks overviewReceive eye mask Jitter tolerance masksAbsolute amplitude Normalized time in UIPeak-to SinusoidalJitter Frequency in kHzTransmitter signal characteristics Signal characteristica Units GbpsReceiver signal characteristics Signal characteristic Units GbpsMaximum allowable jitter Gbps m, n Deterministic jitterqImpedance specifications Receiver jitter toleranceCompliant 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 Cheetah T10 SAS Product Manual, Rev. a Seagate Technology support services Warranty ServiceInternet MySeagate Spp.seagate.com Presales SupportData Recovery Services Authorized Service Centers Data Recovery ServicesToll-free support numbers FAX services-All Europe toll callCall center Presales and Technical Support Warranty Service Africa/Middle East support services Index NumericsPage SAS See also cooling Page Seagate Technology LLC

ST3300555SS, ST3146755SS, ST373355SS specifications

The Seagate ST373355SS, ST3146755SS, and ST3300555SS represent a range of high-performance hard drives designed for enterprise applications, particularly in server environments requiring reliability, speed, and high capacity.

The ST373355SS is a 73.5 GB SCSI hard drive operating at 15,000 RPM, which ensures rapid data access and superior performance, making it ideal for transactional applications and data-intensive tasks. With its 4 MB cache, the drive leverages fast read and write speeds, enhancing overall system responsiveness. The SCSI interface, operating at 80 MB/s, allows for high-speed data transfers, making it a suitable choice for demanding environments where quick access to information is critical. Its hot-swappable feature enables maintenance without shutting down the system, maximizing uptime and productivity.

The ST3146755SS, with a capacity of 146.8 GB, builds on the performance of its predecessor while introducing improvements in data handling and reliability. Operating at the same impressive 15,000 RPM, this model also features a 16 MB cache that greatly improves data throughput and access speed. The drive is designed to reduce latency, which is crucial for applications where timing is everything. It is equipped with advanced error recovery features and Seagate’s innovative PowerTrim technology, which improves power efficiency during read and write operations. The ST3146755SS also features a higher mean time between failures (MTBF), underscoring its reliability in high-demand environments.

Lastly, the ST3300555SS offers even greater capacity with 300 GB. This drive maintains the 15,000 RPM rotation speed and benefits from a 16 MB cache, providing a balance of speed and storage capacity. Its advanced SCSI interface supports not just speed but also data integrity, ensuring consistent performance during extensive data transfers. The drive is designed to handle workloads naturally associated with enterprise servers, data warehouses, and video editing applications. Its rugged build supports continuous operation and is tested for high-temperature environments to ensure durability.

In summary, the Seagate ST373355SS, ST3146755SS, and ST3300555SS hard drives are engineered for enterprise environments, combining impressive RPM speeds, significant storage capacities, and advanced technologies to deliver reliability, performance, and efficiency for critical applications. These hard drives represent Seagate's commitment to providing solutions that meet the rigorous demands of modern data environments.
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