IBM C4C 4.51 3.5-inch Small FF 38-pin Unitized, SSA manual Theoretical Data Sector Transfer Rate

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U S E R RESPONSIBLE F O R V E R I F Y I N G VERSION A N D COMPLETENESS

O E M F U N C T I O N A L S P E C I F I C A T I O N U L T R A S T A R X P ( D F H C ) SSA M O D E L S 1.12/2.25 G B - 1.0" H I G H

3.3.2.1 Theoretical Data Sector Transfer Rate

This Rate does not account for time required for error recovery or defective sectors (the Typical Data Sector Transfer Rate described in 3.3.1, “Basic Component Descriptions” onpage 40 does include those effects). Each group of cylinders with a different number of gross sectors per track is called a notch. The following shows values for notch #1 of C4x models. The "Average" values used in this specification are sums of the individual notch values weighted by the number of LBAs in the associated notches. For the other notches and block lengths use values that correspond to those notches and block lengths.

Data Sector Transfer Rate	=
		Bytes/cylinder

	time for 1 cyl + track skews + 1 cyl skew
Bytes/cylinder	=	{(tracks/cyl)(gross sectors/track) - spares/cyl}(user bytes/sector)
	=	{(16)(135) - 40}(512)
	=	1,085,440 Bytes/cyl
time for 1 cyl of data	=	{(tracks/cyl)(gross sectors/track) - spares/cyl}(avg. sector time)
	=	{(16)(135) - 40}(.061705)
	=	130.815 msec/cyl
time for track skews	=	(tracks/cyl - 1)(track skew)(avg. sector time)
	=	(16-1)(13)(.061700)
	=	12.032 msec/cyl
time for 1 cyl skew	=	(cylinder skew)(avg. sector time)
	=	(25)(.061705)
	=	1.543 msec/cyl
Data Sector Transfer Rate	=

1,085,440 Bytes

130.815 msec + 12.032 msec + 1.543 msec

= 7.517 MB/sec (Notch #1)

Note: See 2.0, “Specifications” on page 11 for thedescriptions of

tracks/cyl (trk/cyl)

gross sectors/track (gs/trk) spares/cyl (b1spr/cyl and b2spr/cyl) user bytes/sector (ub/sct)

gross bytes/sector (gb/sct)

See 3.5, “Skew” onpage 46 for the descriptions of

track skew (tss) cylinder skew (css)

Average sector times per notch can be calculated as follows:

average sector time (ast) =

1sec

120.045 × gs/ trk

3.4Approximating Performance for Different Environments

Source filename=PERFORM

I B M Corporation

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Contents Form Factor Disk Drive Version BM Corporation Preface Source filename=STSSHEXT When Operating Limits ReliabilityContaminants Acoustic Levels Source filename=STSSHEXT Description FeaturesGeneral Features Interface Controller FeaturesModels Reliability FeaturesGeneral SpecificationsSectors/track sct/trk User bytes/sector ub/sctSectors/logical block sct/lba User bytes/logical block ub/lbaFor Each Notch Capacity EquationsFor Entire Drive + 1 2 Volts Supply Power Requirements by Model1 C1x Models Input Voltage + 5 Volts SupplyExample 3. Power Calculation Power Calculation ExamplesExample 1. Calculate the mean 12 volt average current Example 4. Calculate the 12 volt peak current Things to check when measuring 12 V supply currentVolt current during read/write operations C1x Models Typical 12 volt current C1x Models Typical 12 volt spin-up current C1x Models 2 C2x Models Power Calculation Examples Example 4. Calculate the 12 volt peak current Volt current during read/write operations C2x Models Typical 12 volt current C2x Models Typical 12 volt spin-up current C2x Models 3 C4x Models Power Calculation Examples Example 4. Calculate the 12 volt peak current Volt current during read/write operations C4x Models Typical 12 volt current C4x Models Typical 12 volt spin-up current C4x Models CxB Models Power supply methods4.2 DC/DC Converter Hot plug/unplug support Grounding Requirements of the Disk EnclosureM Corporation Event Nominal Maximum Bring-up Sequence and Stop TimesBring-up Sequence Times and Stop Time for C2x Models Source filename=PERFORM # of segments Ub/lba + PerformanceEnvironment Definition Workload DefinitionBasic Component Descriptions Command Execution TimeSequential RandomData Transfer to/from Disk Data Transfer to/from SSA Link CommentsTheoretical Data Sector Transfer Rate Approximating Performance for Different EnvironmentsWhen Read-ahead is Enabled When Read Caching is EnabledWhen Write Caching is Enabled When Adaptive Caching is EnabledBack-To-Back Commands When No Seek is RequiredFor Queued Commands Reordered CommandsCylinder to Cylinder Skew SkewTrack to Track Skew Idle Time Functions Channel Calibration Servo Run Out MeasurementsServo Bias Measurements Predictive Failure AnalysisSave Logs and Pointers Command Timeout LimitsDisk Sweep M Corporation Clearances Weight and DimensionsMechanical Small Form Factor Models CxCDimensions are in millimeters Location of Side Mounting Holes of C4C Models Source filename=MECHANIC Unitized Connector Locations Source filename=MECHANIC Carrier Models CxB Dimensions CxB Models M Corporation Handle Docking and Ejection System Auto-docking Assembly Side Rails Side Rail Positioning E D Locations front view CxB Models M Corporation Electrical Connector and Indicator LocationsElectrical Interface SSA Unitized ConnectorPin Carrier ConnectorRow Option Pins and Indicators SSA Link Electrical CharacteristicsSSA Link Cable Ground long Option Port Pin Device Activity Pin/Indicator Option Port PinDevice Fault Pin/Indicator Option Port Pin Write Protect Option Port PinProgrammable pin 1 Option Port Pin Front Jumper ConnectorEarly Power Off Warning or Power Fail Power Port Pin 12 12V Charge and 5V Charge Power Port pin 1Spindle Synchronization Over Sync Hard-wire M Corporation Source filename=RELIABLE Reliability Error DetectionSeek Error Rate Power On Hours ExamplesProduct Life Power on/off cyclesUseful Life Maximum on/off cyclesSample Failure Rate Projections Install Defect FreeMean Time Between Failure *MTBF Spql Shipped product quality levelESD Protection Periodic MaintenanceConnector Insertion Cycles Install Defect Free percentage PercentOperating Limits Temperature Measurement PointsP F E T Maximum ReliabilityVibration and Shock Temperature Measurement Points for all Models bottom viewOutput Vibration Limits Drive Mounting GuidelinesOperating Vibration V4S Nonoperating VibrationOperating Shock ContaminantsNonoperating Shock Acoustic Levels Upper Limit Sound Power Requirements Bels for C4x ModelsSource filename=STANDARD Standards SafetyElectromagnetic Compatibility EMC M Corporation Serial Storage Architecture S S a P H Transport Bibliography