magnetic tape: technology - slac conferences, … tape ›technology follower - areal density trend...

Magnetic Tape: Technology

Dr. Richard H. Dee

© Copyright 2003 Storage Technology Corporation (StorageTek)

Outline

› Mass Storage Technologies

› Density Trends for Tape (&Disk)

› Capacities/Data rates

› Terabytes on a tape

› Magnetic Recording

› The Media and Heads

› Summary


Mass Storage Technologies

› Magnetic Tape

› Optical Tape

› Magnetic Disk

› Optical Disk (DVD?)

› MEMS Probe

› 3D. Holographic, 2-electron…

› Other


Magnetic Disk› Technology leader (areal density)

› Aggressive storage density growth rate continues but more slowly–100+% CAGR to 60% or even less CAGR predicted–Still a “spoiler” for other storage technologies

› Continued areal density progress influenced by superparamagnetic effect–New approaches to media, heads required, applied, in development

• Research claims up to 50 Tb/in2 !?

› Consumer products effect development, market, cost e.g. “ATA-class disk”

› ATA-class (low-cost) disk can support commercial data processing environment–Utilized in StorageTek’s “BladeStore” disk subsystem with fiber channel rates

CAGR: Compound Annual Growth RateATA: Advanced Technology Attachment

M. Leonhardt 4-9-02


Magnetic Tape› Technology follower - areal density trend lags disk

–Increased defect tolerance–Uses higher media surface area to compete –Volumetric density the tape metric

› Continues to leverage magnetic disk technologies as appropriate

› Opportunity for more aggressive operating points

› Media improvements are key to advancement

› 1TB cartridge capacity product roadmaps target 2005-2007 –Multi-TB’s planned

› Holding on to cost advantage over other storage subsystems types -- low end under pressure from alternatives.

M. Leonhardt 4-9-02


Tape vs. Disk -- “Is tape dead?” -- NO!Reference: Information Storage Industry Consortium (INSIC) Tape Roadmap 2002

› 10 year outlook has tape maintaining its competitive position with disk (within a narrowed market)–Present capacity, data rate ratios can be maintained–Slow down in magnetic disk density advances factored in -- 60% CAGR–Continuing disk innovation assumed -- gets tougher 5-10 years out

M. Leonhardt 4-9-02

282828Data Rate Ratio (Disk/Tape)3.33.33.3Capacity Ratio (Tape/Disk)

TB30.30.03Disk Drive Single Platter CapacityTB1010.1Tape Cartridge Capacity

Unit201120062001Year


The ‘S’ Curve of Technology Progress

T. Schwarz, IEEE-NASA MSS Conference 2000


Areal Density Perspective

1990 1995 2000 2005 20100.1

1

10

100

1000

10000

Charap's Superparamagnetic Limit

||

⊥Perpendicular Recording 1 Tbit/in2

100 Gbit/in2

40-50 Tbit/in2 Single Particle Superparamagnetic Limit

LABORATORY DEMOS

Historical 60% CGR line Products

Max

. Are

al D

ensi

ty (G

bit/i

n2 )

Availability Year

Demos:102 Gbpsi111 Gbpsi

Products:up to 69.8 Gbpsi80GB/3.5”Platter40GB/2.5”Platter

From: Deiter Weller, Mar 2003 Seagate Technology


Areal Density Perspective

From: Amit Itagi, September 2003 Carnegie Mellon University


From: Deiter Weller, Mar 2004 Seagate Technology


Areal Density Trends

0.000

0.001

0.010

0.100

1.000

10.000

100.000

1970 1980 1990 2000 2010 2020Year

Gb/in2

Oxide Media / Ferrite Based

MP Media /FullThin Film Heads

(Thin Film Media/ GMR Heads)

INSIC Roadmaps 1998

MP Limit

trends.xls

2001

1


Volumetric Density Trend

0.1

1

10

100

1000

10000

100000

1970 1980 1990 2000 2010 2020Year

Gb/in3

Volumetric Density69% CAG60% CAG14% CAG10TB Cart

1 Tb/in3

10 TB Cart.


Storage Subsystem End-User Price TrendsUseable Capacity; Mean and Range

$0.01

$0.10

$1.00

$10.00

$100.00

$1,000.00

$10,000.00

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

End

Use

r Pric

e ($

/GB

)

Tape lib. (1/2" mainframe; -36%)

Tape Library (L550/8LTO)

Open RAID 5 (>2TB; -42%)

S390 RAID 1 (>2TB; -50%)

ATA RAID 5 (>2TB; -33%)ATA RAID 5 (<2TB; -33%)

Open RAID 5(<2TB; -42%)

S390 RAID 1 (<2TB; -50%)

Pricing range = 3 standard deviations; normal distribution

Source: IDC, Dataquest, Freeman, StorageTek

ATA RAID 5 as tape (>2TB; -33%)1/2" tape media (ASP)

DLT/LTO media (ASP; -25%)

NGD libraryTape media min.(OEM; -25%)

Tape lib. (DLT/LTO>40; -40%)

Canister ATA RAID 5 (50% margin)

StorageTek Secret

Tape library & media compressed 2XRAID 1 penalty: 100%RAID 5 penalty: 20%RAID 6 penalty: 0%

2002 2006 CAER Ratio of S390 RAID 1 (>2TB) to tape library (DLT/LTO; >40 carts): 47 16 - 23%Ratio of ATA RAID 5 (>2TB) to tape library (DLT/LTO; >40 carts): 8 9 3%

Published: 1/28/2003

ATA disk systems

disk systems

Tape systems

STK Tape Library

ATA disk systems

Tape-disk price convergence stabilized

Proprietary


Disk hardware costs 10X nearline tape per gigabyte

0.1

1

10

100

2004 2005 2006 2007

$/G

igab

yte

DiskNearline tape

10x

Notes:Disk and tape are an entire market averageTape includes library, drives and mediaTape assumes 2X compression

-35% erosion rate

-35% unit price erosion rate combined with a 53% unitshipped growth rate results in flat total market revenue

Source: STK analysis sourced f rom IDC, Dataquest, Meta, Horison

(Slide shown at DLSS Feb 2004 by Bob Raymond)


Capacities and Data Rates

8εNbLCapacity =

8εnbVDataRate =

N = number of tracks, b = bit density, L = length of tape,

ε = efficiency, n =number of channels, V = tape speed


Today….

System STK SDLT LTO -2 IBMT9940B 320 3592

Capacity (TB) 0.20 0.16 0.20 0.30Data Rate (MB/s) 30 16 29 40No. of // Data Channels, n 16 8 8 8Tape Width (mm), W 12.7 12.7 12.7 12.7Tape Length (m), L 648 550 584 580No. of Tracks, N 576 448 512 512TPI 1,411 1,097 1,232 1,233Trk. Pitch (microns) 18.0 23.1 20.6 20.6kBPI, b 157 191 183 277Tape Speed (m/s), v 3.4 2.9 5.4 4.8Areal Density (Gb/sq.in) 0.22 0.21 0.23 0.34Volumetric Density (Tb/sq.in) 0.48 0.41 0.48 0.78


Terabyte Operating Points½"wide tape, 3480/9940 form factor

Capacity (TB) 0.2 0.5 1 5 10 10Data Rate (MB/sec) 30 120 200 300 500 1000No. of Pll Data Channels, n 16 32 32 32 32 64No. of Data Tracks, N 576 768 1152 4750 4140 4140Trk. Pitch (microns) 18.0 14.0 9.3 2.3 2.6 2.6Channel Pitch, c p (microns) 326 164 164 82 82 82Rd. Track Width (microns) 9.0 7.0 4.7 1.1 1.3 1.3Tape Speed, v (m/s) 3.4 4.8 6.0 9.0 8.9 9.0Bit Density, b (kbpi) 159 217 279 298 500 496Track Density (tpi) 1409 1812 2719 11211 9771 9771Areal Density (Gb/in2) 0.22 0.39 0.76 3.35 4.89 4.85Volumetric Density (Tb/in3) 0.48 1.27 2.50 10.70 20.00 20.00Bit Cell (nm) 160 117 91 85 51 51Bit Cell (ns) 47.1 24.4 15.2 9.5 5.7 5.7Write Eq. Pulse (nS) 18.8 9.7 6.1 3.8 2.3 2.3Tape Length (m), L 648 865 865 1000 1400 1400Write Time per Cart. (min) 114 72 87 275 338 168


Linear Density Trend

Fe2O3 650CrO2 650

MP1 1650

MP2 1850

MPX 2400

0

50

100

150

200

250

300

1970 1975 1980 1985 1990 1995 2000 2005 2010Year

kbpi

trends.xls


Recording Theory

Transition from +Mr to –Mr over a distance, a

= −

axMxM r 1tan2)(

π

21

2322

+

=δδ d

HMa

c

r

ArcTangent Transition

-100

-80

-60

-40

-20

0

20

40

60

80

100

-400 -300 -200 -100 0 100 200 300 400

x (nm)

M(x) (emu/cc)

1501005025

a

recording.xls All these parameters are scaling down


Tape Media Progression


Areal Density Limit Calculation for MP Tape

8226.28.212

5216.55.216

3210.43.220

101810171016SNR(dB)

8226.28.212

5216.55.216

3210.43.220

101810171016SNR(dB)Particle Density, p (cm-3)

8000tpi Units: Gb/in2

21

21

lim 32

=SNRptA

Note: This is for conventional MP particles. Spherical particles (e.g. Maxell Nanocap first announced at the INSIC tape meeting at StorageTek Sept 2003) and thin film disk like media extend beyond this.


Terabyte Operating Points½"wide tape, 3480/9940 form factor

Capacity (TB) 0.2 0.5 1 5 10 10Data Rate (MB/sec) 30 120 200 300 500 1000No. of Pll Data Channels, n 16 32 32 32 32 64No. of Data Tracks, N 576 768 1152 4750 4140 4140Trk. Pitch (microns) 18.0 14.0 9.3 2.3 2.6 2.6Channel Pitch, c p (microns) 326 164 164 82 82 82Rd. Track Width (microns) 9.0 7.0 4.7 1.1 1.3 1.3Tape Speed, v (m/s) 3.4 4.8 6.0 9.0 8.9 9.0Bit Density, b (kbpi) 159 217 279 298 500 496Track Density (tpi) 1409 1812 2719 11211 9771 9771Areal Density (Gb/in2) 0.22 0.39 0.76 3.35 4.89 4.85Volumetric Density (Tb/in3) 0.48 1.27 2.50 10.70 20.00 20.00Bit Cell (nm) 160 117 91 85 51 51Bit Cell (ns) 47.1 24.4 15.2 9.5 5.7 5.7Write Eq. Pulse (nS) 18.8 9.7 6.1 3.8 2.3 2.3Tape Length (m), L 648 865 865 1000 1400 1400Write Time per Cart. (min) 114 72 87 275 338 168


GMR Spin Valve Head Data on MP Tape

Recording data compared to model

10

100

1000

10000

100000

0 2000 4000 6000 8000 10000Linear Density (fr/mm)

(µVp-p)SV ModelSV DataDSMR ModelDSMR DataSAL Model


Summary

› Tape continues to lead on volumetric efficiency and $/GByte

› Medium has primary impact on the density growth–Magnetic and physical standpoint

› Head technology in good shape!

› Limit for MP tape ~10Gb/in2

(Careful!! Disk prediction in 1997 36Gb/in2)

›Tape not near any fundamental limits at this time


References

› R. H. Dee, “Magnetic tape recording technology and devices”, Proc. Int’l. Non Volatile Memory Tech. Conference (INVTC), pp.55-64, (1998).

› T. Schwarz, “Magnetic Tape as the Mass Storage Medium”, IEEE-NASA MSS Conference 2000. http://romulus.gsfc.nasa.gov/msst/conf2000/VG/C04VG.PDF

› M. Leonhardt, “Future Directions for Recording Technologies”, THIC Meeting at StorageTek, July 2003. http://www.thic.org/pdf/Jul03/stk.mleonhardt.030722.pdf.

› R. H. Dee, “The challenges of magnetic recording on tape for data storage (The One Terabyte tape and beyond)”, Proc. IEEE/NASA Mass Storage Systems Conf., NASA/CP-2002-210000, pp.109-119, (April 2002).

› R. H. Dee, “Comparison of MR and GMR Spin Valve Heads for Magnetic Recording on MP Tape”, IEEE Trans. Magn. vol.38, pp1922-1924 (2002).

› Dianne McAdam “Debunking the 7 myths of tape” , Data Mobility Group (Feb 2003). http://www.datamobilitygroup.com/

› NIST/ATP Multi-Terabyte Storage http://jazz.nist.gov/atpcf/prjbriefs/prjbrief.cfm?ProjectNumber=00-00-4939

› INSIC http://www.insic.org/tape.htm› Tape Technology Council http://www.tapecouncil.org/index.html

http://romulus.gsfc.nasa.gov/msst/conf2000/VG/C04VG.PDF

http://romulus.gsfc.nasa.gov/msst/conf2000/VG/C04VG.PDF

http://www.thic.org/pdf/Jul03/stk.mleonhardt.030722.pdf

http://www.thic.org/pdf/Jul03/stk.mleonhardt.030722.pdf

http://www.datamobilitygroup.com/

http://jazz.nist.gov/atpcf/prjbriefs/prjbrief.cfm?ProjectNumber=00-00-4939

http://www.insic.org/tape.htm

http://www.tapecouncil.org/index.html

http://www.tapecouncil.org/index.html

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