SAS & SATA Combine to Change the Storage Market€¦ · Harry Mason, LSI Corporation. SAS ... The material contained in this tutorial is copyrighted by the SNIA unless ... Any slide

SAS & SATA Combine to Change the Storage Market

Marty Czekalski, Seagate TechnologyHarry Mason, LSI Corporation

SAS and SATA Combine to Change the Storage Market© 2010 Storage Networking Industry Association. All Rights Reserved.

SNIA Legal Notice

The material contained in this tutorial is copyrighted by the SNIA unless otherwise noted. Member companies and individual members may use this material in presentations and literature under the following conditions:

Any slide or slides used must be reproduced in their entirety without modificationThe SNIA must be acknowledged as the source of any material used in the body of any document containing material from these presentations.

This presentation is a project of the SNIA Education Committee.Neither the author nor the presenter is an attorney and nothing in this presentation is intended to be, or should be construed as legal advice or an opinion of counsel. If you need legal advice or a legal opinion please contact your attorney.The information presented herein represents the author's personal opinion and current understanding of the relevant issues involved. The author, the presenter, and the SNIA do not assume any responsibility or liability for damages arising out of any reliance on or use of this information.

NO WARRANTIES, EXPRESS OR IMPLIED. USE AT YOUR OWN RISK.

22


Abstract

SAS and SATA Combine to Change the Storage MarketSerial Attached SCSI (SAS) allows systems to be built that accommodate large numbers of either SAS and/or SATA hard disk drives. This presentation, intended for OEM, System Builders and End-Users, describes the capabilities of the SAS interface, how it’s designed to interoperate with SATA drives, and when combined, how these technologies can be combined to deliver some very compelling storage solutions.

33


SASPreserving the Past, Creating the Future

Customer Choice• 3.5” and 2.5” form factors• Plug compatible• Multi-protocol

Future Architected• Protocol extends to

new technologies• Serial, switchable• SFF connectors

Usability• Dual-ported• Point-to-point• Cost equal to SCSI

Preserve Legacy SCSI• 25 years of SCSI middleware

Scalable• 1000s of connections

Performance• Wide ports• Low overheard. . .

. . .

z


SAS EvolutionSupporting Key Storage Trends

T10 Specification SAS-1 & SAS1.1 SAS-2

Distinguishing Features Preserves legacy SCSISATA compatibility

3Gb/s compatibleImproved signalingZoning managementImproved scalability

Storage Features Supported/Enabled

RAID 6Small Form FactorHPCHigh Capacity SAS DrivesUltra320 SCSI replacementCustomer ChoiceBlade servers

RAS (Data Protection Info)Security (FDE)ClusteringLarger TopologiesSSDsVirtualizationExternal storage4K Sector sizesMulti-core complex

Expands SAS

beyond traditionalDAS Usage


Blind Mating and Hot Pluggable

SATA Disk ConnectorsSuitable for Both 3.5” and 2.5” Storage Devices Includes data and voltage connectionsHot-Pluggable (staggered pins)Blind Mating

6

Enclosure

~3msec

Drive

Vcc

VccStaged Power

Grounds

Data Pins Voltage PinsRx Tx 3.3V 5V R 12V

Key

Pre-charge


SAS/SATA Compatibility

7

Disk Drive Connectors

SAS

SATAPort B

SAS Connector Flip Side

Accommodates both SAS & SATA Drives

Pluggable

SAS Backplane Connector


World-wide HDD Shipments

8

Enterprise Applications (2008-2012 )(all form-factors by interface)

(M’s)

Potentially Serviceable by SAS

SAS and SATA Combine to Change the Storage Market© 2010 Storage Networking Industry Association. All Rights Reserved. 9

Storage Growth & Innovation Drives Customer Choices

Virtualization

Direct-Attached Storage (DAS)

Networked-AttachedStorage (NAS)

Virtualization and Live Migration Drive Networked Storage

Prevailing Wisdom: Storage Consolidation was accomplished through networked storage solutions (NAS and SAN)

Application intelligence driving applications back to DAS to reduce cost and complexity

Application Intelligence


DAS Deployments (Drive interfaces by volume)

SAN & NAS Deployments(Drive interfaces by volume)

2001 ~70%(SCSI, P-ATA)

~30%(FC, SCSI, P-ATA)

2007 ~70%(3Gb/s SAS, SCSI, SATA)

~30%(FC, 3Gb/s SAS, SATA)

2013 TBD %(6Gb/s SAS, SATA)

TBD % (6Gb/s SAS, SATA)

Market Drivers

• Application intelligence• Price/Power/Performance• NAS on SHV Servers• DAS & S/W improvements• SSD’s

• Virtualization• Ease of use• Pervasive networks• Infrastructure Convergence

10

Who Consumes Enterprise Drives?


SAS’s Unique Attributes

11

CompellingSolutions

Performance

Density (power)

Scalability

SAS and SATA Combine to Change the Storage Market© 2010 Storage Networking Industry Association. All Rights Reserved. 12

SAS: Bandwidth Aggregation

Wide-Port (x4) yields 48Gb/s Full Duplex!

Performance

Bandwidth DOUBLES with 6Gb/s SAS!

Each SAS Link (Rx and Tx)3Gb/s > 6Gb/s (full-duplex)6Gb/s > 12Gb/s (full-duplex)

Wide PortsCombine SAS links (6Gb/s SAS)

2 ports > 24Gb/s (full duplex)4 ports > 48Gb/s (full-duplex)

Concurrency Brings Higher Performance Multiple concurrent I/O’s(lots of drives operating concurrently)


Demonstrating SAS Infrastructure

13

Demonstrates the extremely high throughput available with standard high-volume components

System ComponentsOne Quad-Core processorPCI-Express 2.03 – 6Gb/s SAS Controllers30 Drives (2.5” 6Gb/s 15K RPM, JBOD)Workstation motherboard using latest CPU & chipsetWindows 2003

Performance

i7

PerformanceIometer Throughput Benchmarks

2KB sequential read or write(1,000,000 IOPs)256KB sequential read or write(6.5 Gb/s)


6Gb/s SAS: Significance to SSDs

PerformanceHigh bandwidth and IOPSYears of software refinementAdvancements for low latency storageMultiLink SAS for SSDs

Time to MarketEstablished softwareLow integration riskRapid system qualificationStandards already exist

Enterprise AttributesScalability, Availability, Usability, Serviceability, ReliabilityInfrastructure supports large scale-outsFlexible Connectivity Options

Technology Neutral - Market ResilienceFeatures migrate seamlessly across OS’s & devicesEffective platform for spurring innovation

14

Performance


SAS Backplane Controller Projections– No SAS Changes

2010 2011 20122009

Perf

orm

ance

(4K

Seq

uent

ial I

OPS

)

Feature Functionality

2013

Performance

15

6G900+K

450+K

3G

6G

80+K

150+K

300+K

12G

Additional Improvements Expected• Protocol execution• Application hints• OS improvements• Controller caching• Improvements for external storage systems

6-10X performance gains in ~3 yearsSingle-chip SAS controller performance across PCIe


Latency Comparison:Flash-1 (SAS) vs Flash-2 (PCIe)

Latency measured with VDBench under Win2K8

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

- 40,000 80,000 120,000 160,000 200,000

I/O

Lat

ency

, ms

per

I/O

Measured Load, IOPs

Flash-1 Response Time -> Throughput, Win2K8

1 Th 4K Seq Wr 4 Th 4K Seq Wr 8 Th 4K Seq Wr 16 Th 4K Seq Wr32 Th 4K Seq Wr 64 Th 4K Seq Wr 128 Th 4K Seq Wr

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

0 40,000 80,000 120,000 160,000 200,000

I/O

Lat

ency

, ms

per

I/O

Measured Load, IOPs


1 Th 4K Seq Wr 4 Th 4K Seq Wr 8 Th 4K Seq Wr 16 Th 4K Seq Wr32 Th 4K Seq Wr 64 Th 4K Seq Wr 128 Th 4K Seq Wr

Threads ≥ 8 SAS = lower latency

Threads ≤ 8 PCIe = lower latency

Latency dependent upon:Offered load (4K Seq Write)Queue or thread depth (multiple thread sizes)

SAS Concurrency favors enterprise workloads16


Latency Comparison:Flash-1(SAS) vs Flash-2 (PCIe)

0

1

2

3

4

5

6

7

8

0 200 400 600 800 1,000 1,200

I/O

Lat

ency

, ms

per

I/O

Measured Load, MB/s


1 Th 64K Rnd Rd 4 Th 64K Rnd Rd 8 Th 64K Rnd Rd 16 Th 64K Rnd Rd32 Th 64K Rnd Rd 64 Th 64K Rnd Rd 128 Th 64K Rnd Rd

0

1

2

3

4

5

6

7

8

0 200 400 600 800 1,000 1,200

I/O

Lat

ency

, ms

per

I/O

Measured Load, MB/s


1 Th 64K Rnd Rd 4 Th 64K Rnd Rd 8 Th 64K Rnd Rd 16 Th 64K Rnd Rd32 Th 64K Rnd Rd 64 Th 64K Rnd Rd 128 Th 64K Rnd Rd

Latency dependent upon:Offered load (64K Random Read)Queue or thread depth (multiple thread sizes)

Threads ≥ 4 SAS = lower latency

Threads ≤ 4 PCIe = lower latency

SAS Concurrency favors enterprise workloads

Latency measured with VDBench under Win2K8

17


SAS/SATA SSD Market Share

Source: IDC

Enterprise Shipments (Volume)Performance

18


Industry Compacts Storage

SAS & Small Form Factor (2.5”)Increased Density

Scale & expand in same spaceIdeal for Blade systems

50% less power than 3.5” DrivesLower heat loads & cooling costs at equivalent performance (Caution – power per rack can still increase due to density increase)

More IOPs & Lower CostDrives operating concurrently creates better performanceLower TCO through common infrastructure

Features and FlexibilityRAID 5 or 6 on a 1U serverSAS & SATA drives in common drive carrierCo-exists with SSDs

19

Requested update from IDC

M’s

of U

nits

Density


Connector Types

20

SAS 4X ConnectorExternal Mini-SASInfiniBand

Preferred externalconnection scheme for 6Gb/s SAS

Density

SAS 4X Connector


Scaling outside the Server

21

SASController and/or

SAS Cables

Expand Your DAS Capabilities

Cascaded Enclosures

Density


SAS: Improving Density and Airflow

22

SAS dramatically improves connectivity, density & airflow.

Up to 160 SAS links per 1U rack!

SATA/SAS cablevs parallel

External & Internal SAS 1.1 Mini-SAS (4x & 4i)

Highly scalable architectureconnectivity and bandwidth

Density


Self ConfiguringExpanders Extend SAS

23

1st Gen SAS DiscoveryVendor-unique zoningLimited to 128Discovery executed by initiator end-devices

Complicated large topologies Problematic for zoning

2nd Gen SAS DiscoveryStandardized zoningExpanded to 1KDiscovery executed by SAS expanders

Reduces time to discover large topologiesEases burden on IO flow due to disk add/pullEnables zoning of the topology

Scalability

Enables richer SAS technologies!

SAS/SATA(Target)

Zone A

Zone B

SAS/SATA(Target)

SAS/SATA(Target)

SAS/SATA(Target)

SAS/SATA(Target)

SAS/SATA(Target)

Host(Initiator)

Host(Initiator)


Host AttachSAN or NAS or SAS

Scaling SAS Architecture

24

SAS Switch (packaged view)

SAS Switch

SAS HDDs

Various JBODs

Embedded ControllersSAS Connected

Scalability

SATA HDDs

SATA HDDs

SATA HDDs

SATA HDDs

SATA HDDs

SATA HDDs


Switched SAS Applications

25

RAID Array Drive Expansion

Blade Storage Mid-plane I/F

Shareable DASSolutions

External Storage

SAS Switch

SAS SwitchLower Cost

Higher Bandwidth

Expander

Expander

Blade ServerBlade ServerBlade ServerBlade ServerBlade ServerBlade ServerBlade ServerBlade ServerBlade ServerBlade ServerBlade ServerBlade ServerBlade ServerBlade Server

Daughter Card

SASController

RAID Controller

ExpanderSAS ROC

RAID Controller

ExpanderSAS ROC


Benefits of Switched SAS

Centralized ManagementReliability

Improvement over cascaded connections

Legacy protection/isolationScalability

Thousands of storage devices

AvailabilityReduce latency and bottlenecks –improve fairness

26

Solutions


Scalable, Sharable DASSAS Value Proposition & Positioning

Significant market segment underserved by SAN alternativesSame room, modest scale (Few 10’s of servers & several 100’s drives)Compliments Application Intelligence and Application MessagingEnhances Clustered ApplicationsShorter distances = less power (use it only where you need it)

27

Performance Low Cost Distance

Fibre Channel X XGbE iSCSI X X10 GbE iSCSI X XSAS X X x

Solutions


SAS & SATA Span the Storage Spectrum

28

• Controllers/ROCs• Expanders• SAS/SATA HDDs• SAS/SATA SSDs• Storage blades

• Expanders • SAS switches• Bridges• Port multiplexers

• NAS/SAN heads• Native SAS connect• Controllers/ROCs• Expanders• SAS/SATA HDDs• SAS/SATA SSDs• SAS/SATA Tape

• SAS drives• SATA drives• Near-line SAS • Drive carriers• Drive controllers

SAS/SATA Connectivity Creates Tiered Storage Solutions

Direct Attach Storage External StorageSAS Fabrics HDD/SSD


What’s coming?

High Capacity SAS - Simplifies SAS ArchitectureSAS interface on high capacity drives, 2 TB and higherArchitecturally more efficient, improves enterprise system integrity

12Gb/s SAS - Doubles transfer rate6Gb/s and 3Gb/s SATA compatibleSpecification advancing in T10On schedule for mid-2012 plugfest

SAS Advanced Connectivity Mini-SAS HD SolutionsActive Copper to 20m/Optical to 100m

Multilink SAS for Solid State Disks (SSD)Backward compatible backplane connectorMeets/exceeds SSD performance requirements

29


SAS Advanced Connectivity Objectives

Drive market consistencySimplify cable and connector options Provide converged high-density connectivityProvide managed connectivity standardsProvide active copper solution to 20mProvide optical solution to 100mSupport 6Gb/s SAS deploymentsExtensible to 12Gb/s SAS deployments

Cable providesactive component

for optical or copper

Mini-SAS HD connectors courtesy:Project T10/2125-D Revision 04

17 September 2009, ANSI SAS-2.1

Internal similar to External

Supply power here for active cabling

SAS-2.1 standardizes OOB for active cables Passive, Active Copper, or

Optical use same connector

30


SAS Advanced Connectivity

31


MultiLink SAS Initiative

STA endorsed May 2010 Defines new type of SAS drive slot

Increased power/slotMultiple SAS links

No protocol changes (desired)Work with existing infrastructure components

Options for 12Gb/s and 24Gb/s link performance

32


Proposed MultiLink Solution

Current 2-Port SAS Receptacle Configuration

Proposed 4-Port SAS Receptacle Configuration

Port 1 – Signal(7 Pins)

Port 1 – Power(15 Pins)


Port 3 & Port 4 – Signals(13 Pins)



Port 1 – Power(15 Pins)


MultiLink SAS Slot

SSD

SSD

SSD

SSD

34www.scsita.org

MultiLink SAS Connector

MultiLink SASHigh performance (20+W per slot)Hot swap, serviceabilityHigh availability (2 fault domains possible)Low implementation risk:

Standard SAS driversFully hardened protocol stackCommon Management Stack

Low investment (repackaging)Flexible: Independent SSDs or wide-port SSDsAble to isolate tier-tier traffic w/o accessing system memory


MultiLink SAS timetable

Validation and Proposals to

T10 & SFF

Kick-off

Demos and prototypes

OEM System Integration and Qualifications

12Gb/s SAS Plugfest

Refreshed server platforms

New server platforms

www.scsita.org

2010 201320122011

35


MultiLink SAS Roadmap:Backplane Slot Connector

www.scsita.org

3Gb/s(1x1)

Legacy Slot Compatible

6Gb/s(2x1)

12Gb/s(2x2)

24 Gb/s(2x4)

New Slot

36

MultiLink SAS

Existing Connector

1

10

100

1000

6

24

96

384

Ban

dwid

th (G

b/s,

Ful

l Dup

lex)


Additional Info Available at:

37

T10 (SAS specifications development)http://www.t10.org

SCSI Trade Associationhttp://www.scsita.org

Serial Storage Wire)http://www.serialstoragewire.net

SATA I/Ohttp://www.sata-io.org

http://www.t10.org

http://www.scsita.org

http://www.serialstoragewire.com

http://www.sata-io.org


Q&A / Feedback

Please send any questions or comments on this presentation to SNIA: [email protected]

3838

Many thanks to the following individuals for their contributions to this tutorial.

- SNIA Education Committee

Marty Czekalski Terry GibbonsChas Gimarc Scott ShueyHarry Mason Nancy ClayJay Neer MultiLink Working Group

mailto:[email protected]

Documents

SAS & SATA Combine to Change the Storage Market€¦ · Harry Mason, LSI Corporation. SAS ... The material contained in this tutorial is copyrighted by the SNIA unless ... Any slide