Tape Trends for Enterprise Systems · T3 T2 T1. Digital Storage For The Visual Age Chemistry of...

Digital Storage For The Visual Age

Presented at the THIC Meeting at the Raytheon ITS Auditorium, 1616 McCormick DrUpper Marlboro MD 20774-5301

November 5-6, 2002

Tape Trends for Enterprise SystemsGary Rexroat

Ampex Data Systems1228 Douglas Ave, Redwood City CA 94063-3117

Phone: +1-650-367-3664E-mail: [email protected]


Tape Trends for Enterprise Systems

Gary RexroatAmpex Data SystemsTHIC Meeting [email protected]


Tape Technology and Trends

• Background and use of Tape Technology

• Archive Issues of Tape

• Tape Trends for Enterprise Systems


Tape Design

Lubricants

Smoothness Low errors

Stability

DurabilityOutput

RoughnessStiffness

Cure Chemistry Binders

Young’s Modulus

Particle treatment

Backcoat, engineered roughness

Smoothness

Small particle, high Hc

Headwear, cleaning

Binders

Interchange

Low coefficients of expansion

Long term stable friction

Slitting accuracy

ESD

Robust physically

MP loadingFriction


Tape preparation & coating


Tape Cartridge Assembly & Test

• Incoming inspection and Q.C.• Cleaning • Leadering, loading into inspected

reels • Cartridge parts assembled, along

with reels • Inspect and certify on well

maintained recorders• Passed tapes degaussed then to

final inspection & labeling and packaging


Ampex Media Certification Test

Test Name: qd0008 Date: 05/15/1999 Time: 12:22:30 page 0________________________________________________________________________

DST MEDIA TEST RESULTS (Ver. 4.00) >> AMPEX PROPRIETARY 880: 5 5========================================================================== General System Performance Summary

Head1 Head2 Head3 Head4 TotalC1: 20.6 18.3 29.2 11.2 79.3 (errors / 10 frames)C2: 6.9 6.0 5.0 3.4 21.4 (errors / 10 frames)

Total Number of C3 Corrections: 9797 CRC Failures: 0

Average Error Rate (based on C1, C2, and C3): 1.35E-05========================================================================== Results Summary

Parameter Actual Limit Pass/Fail ========= ====== ===== =========Cartridge Capacity 25.8 25 PASSTotal Failures 6 6 PASSHard Failures 0 2 PASSSoft Failures 6Flying Clogs 0 0 PASSPermanent Clogs 0 0 PASSC1 Max per head 29.2 300 PASSC1 Average/head 19.8 200 PASSC2 Channel Ratio 1.3 10 PASS

Total Failed Parameters: 0

Detailed Analysis of Physical Blocks that Caused Rewrites

C2 Corrections C2 Erasures C3 CRC Worst ADFN Hd1 Hd2 Hd3 Hd4 Hd1 Hd2 Hd3 Hd4 Corr. Fail C2--------------------------------------------------------------------------- 2304 1157 0 0 0 0 0 0 0 0 0 1157 11620 1309 0 23 1295 269 0 0 0 2387 0 1309 15661 1773 0 0 62 0 0 0 0 0 0 1773 15662 0 519 1619 0 0 372 0 0 3063 0 1619 18876 0 0 19 0 0 0 438 0 4347 0 19 23535 2014 0 0 239 0 0 0 0 0 0 2014


Ampex Data Error Certification SystemPhysical block size, 32 tracks

1. C2 errors > _x_ corrections/ _y_ tracks, or 2. C2 fails to correct 1 track in 32

Rewrite criteria met?yes no

No. of C2 corrections of “worst” headNo. of C2 corrections of “best” head

> 10 ?

yes no

Soft failure Hard failure

yes no

C2 erasures for “worst” head continues > _x_ PB’s, but < _y_ PB’s

Flying clog

Permanent clog

C2 erasures for “worst” head continues > _y_ PB’s


Archivability

• Temperature AND Humidity are important• Chemistry

– Water + Ester = Alcohol + Organic Acid– New binders help to prevent this

• Accelerated aging studies– What are they? – How good are they?


“Generally Recognized as Safe” Recommendation

• Operating:– 50 ºF to 86 ºF– 20 %RH to 80 %RH

• Long term archive:– 70 ºF and 20 %RH– 60 ºF and 30 %RH– 50 ºF and 40 %RH


Temperature & Humidity trade-off

T1T2T3


Chemistry of binder breakdown

• Polyester goes to an alcohol & an organic acid


Acquisition - To – Archive, Multi-Data Types

GLOBAL HAWK HAE UAV IMAGERY

On Board Data Acquisition

DCRsi 75Digital Recorder

System or

Disk or Solid State

Recorder System

Ground Processing Station

DST 714Imagery & File Archive

DCRsi - DDRsdirect data dubbing to Archive or data replay for processing.


Ampex Network Attached Storage


Tape Trends

• Cost per GB to customer decreasing• Thinner tapes• Single reel cartridges• Library robotic environments

– Robust tape and robust drives– Interchange– Need for fast access


Storage Media Costs


MP Tape Formats Trend

Mag

Coat

ing

Mag

Roug

hnes

s

Base

film

thic

k

Tape

leng

th

Format1Format2Format3

Thinner, smoother tapes result in longer tapes with higher output for greater capacity


Thinner tapes, magnetic layer• Thin coatings

– MP ++ tapes• 3 µm down to 0.3 or 0.1 µm • “dual” or “slot die” coating results in smoother, highly durable

surface

– AME tapes• expensive evaporation process• multilayers: underlayers and overlayers• easy to get very thin, smooth surface


Thinner tapes, basefilmProperty PET PEN PolyAramid

Young’s modulus(kg/mm2)

600 800 1300

Heat shrinkage 4 5 0.2

Thermal coef.Expansion (per°C)

5x10-6 5x10-6 8x10-6

Hygroscopic coef.Expansion (per°C)

10x10-6 10x10-6 10x10-6

Cost (by wt.) 1X 4X 25 – 30X


Data access = data rate and more...

0 50 100 150 200 250 300

seconds

IBM LTO

S-DLT

Ampex Quad DST

Load time to BOTAver file access (from BOT)Write 100 MBMaximum rewind timeUnload from BOT

80 seconds

271 seconds

226 seconds

Single Reel vs. Double Reel Cartridge


No Full Tape Rewind: DST Tape Partitioning

• System Zones- Provides non-data areas for scanner thread/unthread

• Partitions- Treated as logical volumes- Can be independently updated to utilize tape capacity

• Purpose- Performance enhancement- Reliability enhancement

Increases performance by eliminating full tape rewinds, fast ejects


Library Environments for Tape

DST® 4144.8 TB

DST® 71411.6 TB

DST® 81425.6 TB

DST® 91426.1 TB

Tape and tape drives must meet rigorous challenges of :• Interchange• Robust construction• Long life


1.6 Petabyte Archive - ADIC /DST Drives


Prevue Network - HSM and Backup Solution


Accurate Tape Interchange

• Air Bearing Guides• Stainless Steel Guide Band• Tape Drive Chassis that is precision ground & measured at

the factory• Tape straightness & dimensional stability

– AST™ Play Head– DSP servo’s

Tapes written by native recorder may need to be read by many different recorders in a library environment


Air-lubricated Tape Guiding

• Air guides provide gentle tape handling

• No “steering” as with mechanical bearing/ rollers

• Stainless Steel guide band ensures precise track-to-head alignment

• Both together enables accurate tape interchange


Rugged, Precision Transport

• ZEISS coordinate measuring machine probes each DST®transport 500 times during factory test using six computer programs

• Chassis is precision ground and manufactured to 0.5 µm tolerances

• Materials for chassis chosen for low thermal expansion and long-lasting stiffness and resistance to mechanical change over time

• All transports 100% verified


AST™ Heads & DSP eliminate changes in tape• Read heads have servo

mechanism & electronics that position the head dynamically in realtime with any track curvature

• DSP servo systems designed into each Ampex DST drive

• Together, errors due to track curvature are virtually eliminated


1990 1992 1994 1996 1998 2000 2002 2004 2006 20080

1

2

3

4

5

Medium Cassette Capacity Road Map

year

capa

city

, ter

a by

tes

single densitydouble density quad density

terabyteformat

(200 kbpi, 11 micron tracks)

(200 kbpi, 5.5 micron tracks)

(200 kbpi, 5.5 micron tracks)

PEN substrate tape

dual-coating MP tape

Ampex DST Recorder Road Map


In Conclusion• Tape is good• Tape has been determined to be safe to store for >30 years

under controlled archival storage conditions (don’t forget to include the drive!)

• Tapes below 4 or 5 um may present cost challenges to the reduced $/GB trend

• Multi-cartridge and multi-drive library environments will dictate added requirements for the tape and tape drive– Robust tape and drive– Tape interchange must be maintained– Fast access


Thank You

Tape Trends for Enterprise Systems · T3 T2 T1. Digital Storage For The Visual Age Chemistry of...

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