Seagate ST9600204FC, ST9450404FC, ST300MM0026, ST900MM0036, ST900MM0026, ST600MM0026 manual 77.87

Page 42

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 4 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 4: Read and write retry count maximum recovery times

Read retry count1

Maximum recovery time per

LBA (cumulative, ms)

 

 

 

0

 

77.87

 

 

 

1

 

89.85

 

 

 

2

 

305.49

 

 

 

3

 

347.42

 

 

 

4

 

472.94

 

 

 

5

 

512.32

 

 

 

6

 

560.24

 

 

 

7

 

701.17

 

 

 

8

 

803.25

 

 

 

9

 

851.17

 

 

 

10

 

893.10

 

 

 

11

 

1115.08

 

 

 

12

(default)

2106.65

 

 

 

Write retry count1

Maximum recovery time per

LBA (cumulative, ms)

 

 

0

35.94

 

 

1

53.91

 

 

2

79.89

 

 

3

97.86

 

 

4

175.85

 

 

5 (default)

421.79

 

 

[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 442.89ms recovery time for each of the four LBAs in the command. If the recovery time limit is set to 00 C8 hex (200ms decimal) a four LBA read command is allowed to take up to 200ms 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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Savvio 10K.4 FC Product Manual, Rev. A

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Contents Savvio 10K.4 FC ST9600204FC ST9450404FCRevision history Rev. a 03/26/10 Initial releaseContents Installation Seagate Technology support services Savvio 10K.4 FC Product Manual, Rev. a Scope Electromagnetic compatibility Standards, compliance and reference documentsStandards Electromagnetic susceptibilityEuropean Union Restriction of Hazardous Substances RoHS Reference documents Ncits TR-19General description Standard features Media descriptionPerformance ReliabilityFormatted capacities Factory-installed options User-installed accessoriesProgrammable drive capacity Access time Performance characteristicsInternal drive characteristics Seek performanceStart/stop time Format command execution time minutesGeneral performance characteristics Prefetch/multi-segmented cache controlCache operation Caching write data Prefetch operationRecoverable Errors Reliability specificationsError rates Unrecoverable ErrorsInterface errors Reliability and serviceSeek errors Preventive maintenance4 S.M.A.R.T Controlling S.M.A.R.TPerformance impact Predictive 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 AbortPhysical/electrical specifications PowerChoiceTM power managementPowerChoice modes AC power requirements DC power requirements DC power requirements for ST9600204FC model 2Gb 4Gb AmpsDC power requirements for ST9450404FC model 2Gb 4Gb Amps General DC power requirement notes Power sequencingConducted noise immunity Current profiles Savvio 10K.4 FC Product Manual, Rev. a Power dissipation ST9600204FCST9450404FC Temperature a. Operating Environmental limitsRelative humidity Effective altitude sea level a. Operating Shock and vibrationShock 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 dimensionsDefect and error management Drive internal defects/errorsDrive error recovery procedures 77.87 FC-AL system errors Background Media ScanMedia Pre-Scan Deferred Auto-Reallocation Idle Read After WriteDrive orientation InstallationDrive ID/option selection CoolingDrive mounting Air flowGrounding Link services supported Type of frame FC-AL featuresFibre Channel link service frames Interface requirementsFibre Channel task management functions Fibre Channel task management responsesFC 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 Savvio 10K.4 FC Product Manual, Rev. a Temperature page 0Dh Mode Sense data Inquiry dataSavvio 10K.4 FC inquiry data Bytes Data hex Page Mode Data Header 34 65 f8 70 00 00 02 Miscellaneous operating features and conditions Supported Feature or conditionPhysical characteristics FC-AL physical interfacePhysical description Connector requirements Electrical descriptionPin descriptions FC-SCA pin descriptions Pin Signal name Signal type FC-AL transmitters and receiversPower Fault LED OutEnable port bypass signals Active LED OutMotor start controls Parallel Enclosure Services Interface ESI 11 SEL6 through SEL0 ID linesAlpa SEL ID Signal characteristics TTL input characteristicsDevice control codes LED driver signals FC Differential outputFC Differential input Receive eye diagram Eye diagram data values Link rate GHz Seagate Technology support services Warranty Support Direct.seagate.com Spp.seagate.comWeb Data Recovery Services Call Center Toll-free Direct dial Technical Support Warranty ServiceData Recovery Services Authorized Service Centers Presales SupportSavvio 10K.4 FC Product Manual, Rev. a Index FCP Flogi Plogi Page See also cooling Page Seagate Technology LLC
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