Seagate ST3450802FC, ST3300602FC, ST3600002FC manual 77.81

Page 46

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

77.81

 

 

1

89.78

 

 

2

305.24

 

 

3

347.13

 

 

4

442.89

 

 

5

490.77

 

 

6

538.65

 

 

7

670.32

 

 

8

807.98

 

 

9

855.86

 

 

10

897.75

 

 

11 (default)

2370.04

 

 

Write retry count1

Maximum recovery time per

LBA (cumulative, msec)

 

 

0

35.91

 

 

1

53.865

 

 

2

83.79

 

 

3

101.745

 

 

4

179.655

 

 

5 (default)

221.55

 

 

[1]These values are subject to change.

Setting these retry counts to a value below the default setting could result in an increased unrecovered 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 442.89 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. Therefore, 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 NS 10K.2 FC Product Manual, Rev. B

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Contents Cheetah NS 10K.2 FC ST3600002FC ST3450802FC ST3300602FCPage Contents Installation Seagate Technology support services Cheetah NS 10K.2 FC Product Manual, Rev. B Scope Cheetah NS 10K.2 FC Product Manual, Rev. B Electromagnetic compatibility Standards, compliance and reference documentsStandards Electromagnetic susceptibilityCompliance Reference documents Ncits TR-19Cheetah NS 10K.2 FC Product Manual, Rev. B General description Standard features Media descriptionReliability PerformanceFormatted capacities User-installed accessories Factory-installed optionsProgrammable drive capacity Access time Performance characteristicsInternal drive characteristics Seek performanceStart/stop time Format command execution time minutesGeneral performance characteristics ST3600002FC ST3450802FC ST3300602FCPrefetch/multi-segmented cache control Cache operationCaching write data Prefetch operationRecoverable Errors Reliability specificationsError rates Unrecoverable ErrorsInterface errors Reliability and serviceSeek errors Preventive maintenanceControlling S.M.A.R.T A.R.T. delay times4 S.M.A.R.T Performance impactPredictive failures Reporting controlDetermining rate Thermal monitorDrive Self Test DST State of the drive prior to testingTemperature Log Page 0Dh DST failure definitionShort test Function Code 001b Invoking DSTShort and extended tests Extended test Function Code 010bProduct warranty AbortCheetah NS 10K.2 FC Product Manual, Rev. B DC power requirements Physical/electrical specificationsAC power requirements DC power requirements for ST3600002FC model Gbit AmpsDC power requirements for ST3450802FC model Gbit Amps General DC power requirement notes DC power requirements for ST3300602FC model Gbit AmpsConducted noise immunity Power sequencingCurrent profiles Cheetah NS 10K.2 FC Product Manual, Rev. B Cheetah NS 10K.2 FC Product Manual, Rev. B Power dissipation ST3600002FCST3450802FC ST3300602FC Environmental limits Temperature a. OperatingRelative humidity Shock and vibration Effective altitude sea level a. OperatingShock Package size Packaged/product weight Drop height Recommended mountingAcoustics Air cleanlinessVibration a. Operating-normal Corrosive environmentChina Restriction of Hazardous Substances RoHS Directive Mechanical specifications Mounting configuration dimensionsCheetah NS 10K.2 FC Product Manual, Rev. B Drive internal defects/errors Defect and error managementDrive error recovery procedures 77.81 Background Media Scan FC-AL system errorsMedia Pre-Scan Deferred Auto-Reallocation Idle Read After WriteDrive orientation InstallationDrive ID/option selection CoolingDrive mounting Air flowGrounding Cheetah NS 10K.2 FC Product Manual, Rev. B Link services supported Type of frame FC-AL featuresFibre Channel link service frames Interface requirementsFibre Channel task management responses Fibre Channel task management functionsFC Scsi FCP response codes Function name Response code Fibre Channel port login NPort login Plogi payload BytesNPort Login Accept ACC payload Bytes Fibre Channel port login acceptFibre Channel Process Login Process Login Plri payloadProcess Login Accept ACC payload Bytes Fibre Channel Process Login AcceptFibre Channel fabric login Fabric Login Flogi payload BytesFibre Channel fabric accept login Fabric Login Accept ACC payload BytesFC-AL options supported Dual port supportFibre Channel Arbitrated Loop options Option SupportedScsi commands supported Supported commands Command code Command nameVerify error recovery page 07h Cheetah NS 10K.2 FC Product Manual, Rev. B Temperature page 0Dh Inquiry data Mode Sense dataCheetah NS 10K.2 FC inquiry data Bytes Data hex Page Mode Data Header Mode Pages 00 00 05 12 8B 00 50 Miscellaneous operating features and conditions Supported Feature or conditionFC-AL physical interface Physical characteristicsPhysical description Electrical description Connector requirementsPin descriptions FC-SCA pin descriptions Pin Signal name Signal type FC-AL transmitters and receiversPower Fault LED OutActive LED Out Enable port bypass signalsMotor start controls Parallel Enclosure Services Interface ESI 11 SEL6 through SEL0 ID linesAlpa SEL ID TTL input characteristics Signal characteristicsDevice control codes FC Differential output LED driver signalsFC Differential input Receive eye diagram Eye diagram data values Link rate GHz Cheetah NS 10K.2 FC Product Manual, Rev. B Presales Support Seagate Technology support servicesTechnical Support Data Recovery Services Authorized Service Centers Warranty ServiceData Recovery Services Call Center Toll-free Direct dial Index FCP Flogi Plogi Page See also cooling Page Seagate Technology LLC
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