LSI Logic Serial Attached SCSI (SAS) & SATA Overview

The Emergence of Serial Attached SCSI (SAS) Newest Storage Interface for Direct Attach Storage (DAS) SAS Improves & Builds on Parallel SCSI Foundation Supported by ANSI T10 Standards Committee (Same as SCSI) Successor to Ultra320 SCSI on Industry Roadmap Significant Performance & Feature Set Enhancements Source: SCSI Trade Association Jan 2004 LSI Logic Confidential © LSI Logic 2003

SATA vs SATA300 Feature Comparison Feature List SATA SATA 300 First Party DMA  Native Command Queuing Identify device/set feature Defect management Enclosure management Staggered Spin up Hot Plug/Presence Detect Port Multiplier 1.0 2nd Phy spec 3Gb/s The Serial ATA native queuing model utilizes the First Party DMA mechanism to allow the device to select the appropriate host memory buffer to transfer data to or from. New Serial ATA features and capabilities include a means by which their presence and support can be determined, and a means for enabling them if optionally supported. Defect management, informative, SMART drive staggered spin-up to minimize the power surge when a subsystem powers up. LSI Logic Confidential © LSI Logic 2003

LSI Logic Storage Controllers 2004 2005 2006 1H’05 3.0Gb/s PCI RAID HBA FC 2Gb/s FC 4Gb/s LSI Logic Confidential © LSI Logic 2003

SAS is Compatible with SATA! Feature: SAS controllers can talk to SATA or SAS HD Drives SAS HDD - Used When Performance & Reliability are Critical SATA HDD - Used When Capacity & Cost Are Most Important SAS & SATA HDD - Can be Mixed in Single System Benefit: Server & Workstation Platforms Can be Standardized to Reduce Component Qualification & Inventory LSI Logic Confidential © LSI Logic 2003

SAS & SATA are Interoperable SAS and SATA HDD connectors SATA backplane connectors will NOT accept SAS HDDs SAS backplane connectors accept both SAS target and SATA HDDs Notch is filled in SAS connector No Notch Dual Ported LSI Logic Confidential © LSI Logic 2003

New Terms SATA Architected, SATA Populated (SATA) A system that contains SATA Controllers, SATA HDD, and optionally SATA Multipliers Low cost, GREAT for certain markets (i.e. streaming, archive) SAS Architected, SAS Populated (SAS) A system that contains SAS controllers, SAS HDD, and optionally SAS expanders X3 cost on HDD, top notch performance for IOP intensive applications SAS Architected, SATA Populated (SAS/SATA) A system that contains SAS controllers, SATA HDD, and optionally SAS expanders This allows the creation of sophisticated topologies with low cost SATA HDD LSI Logic Confidential © LSI Logic 2003

The Power of Serial Interfaces SATA 300 SAS w/SATA HDD SAS Feature: Small Connector Enables Small Form Factor HDDs Benefit: More storage per cubic inch  Feature: Small Cable vs SCSI or ATA Benefit: Simpler cabling, better cooling Feature: 3 Gb/s (300 MB/s) ITransfer Rate Increasing to 12 Gb/s (1.2 GB/s) in Successive Generations Benefit: Unprecedented performance and roadmap Feature: Point to Point Connection with Dedicated Bandwidth Benefit: Simplified cabling, NO signal integrity problems LSI Logic Confidential © LSI Logic 2003

 SAS - SCSI on Steroids!! SATA SAS w/SATA HDD SAS Feature: Full Duplex Data Transfer Benefit: FC-like Simultaneous Upstream & Downstream Data Flow Effectively Doubling Performance  Feature: Each HDD is Assigned a Unique World Wide Name (WWN), Similar to FC Benefit: FC-Like SAN capabilities Feature: Dual Ported Benefit: FC-Like Redudancy Feature: SCSI Tagged Command Queuing (256 Levels) Benefit: Old fashioned SCSI performance, with all the benefits of SAS (SATA Native command queuing is GOOD, SCSI Command Queuing is better!!) LSI Logic Confidential © LSI Logic 2003

SAS & SATA - The New Paradigm SAS w/SATA HDD SAS Feature: SAS Supports up to 16,256 Devices in a Domain (128 is more practical) Benefit: Sophisticated topologies including JBOD (SATA II = 15 Devices/ port)  Feature: SAS Cabling Distances of 8m Point to Point (vs. 1m for SATA) Benefit: Enables Box to Box connectivity within a Rack Feature: SAS Expanders (vs SATA Multipliers) Benefit: Allows Tremendous Flexibility in Application Configuration(i.e. JBOD and JBOD Cascading) Feature: Wide Ports - Four Ports of Aggregated Bandwidth Benefit: Unprecedented versatility in design and performance levels LSI Logic Confidential © LSI Logic 2003

Technology Comparison Significant Differences Exist SAS adds FC Capabilities SATA 300 SAS Fibre Channel Performance Half-duplex Full-duplex with Link Aggregation Full Duplex 3.0 Gb/s 3.0 Gb/s Introduction 6.0 Gb/s in 2006 2.0 Gb/s 4 Gb/s in 2004 Connectivity 1 m internal cable > 8 m internal and external cables 15 m external cable (Copper) Multipliers 15 HDD max Expanders >128 devices 127 devices FC-AL 16 Million Fabric Availability Single-port HDDs Dual-port HDDs Dual-port HDDs Single-host Multi-initiator Multi-initiator Driver Model Software transparent with Parallel ATA Software transparent with Parallel SCSI Software transparent with Parallel SCSI LSI Logic Confidential © LSI Logic 2003

SAS Expanders & Wide Ports Are Key!! SAS Wide Ports are Unique in Storage No SCSI, SATA, or FC equivalent A wide port is defined as more than one physical link in a port Wide ports are used to aggregate bandwidth A wide port is a set of 1-4+ physical links between two devices. Different connections may be open on different links. Typical usage: HBA/RAID controller wide port connected to expander wide port All physical links in wide port use the same SAS address Wide ports are transparent to the host/OS Command sent down one link; data may be returned on another link (separate connection). No SW is required, all link arbitration is handled by HW. SCSI Expert?? LSI Logic Confidential © LSI Logic 2003

The Real Power of Wide Ports SATA Multiplier SATA Multiplier SAS Expander Good for Streaming Poor at IOPs Good for Streaming Good for IOPs SATA Controller SAS Controller SAS Expander X1, x2, x3, x4 Host Connection ASx12 is 1x11, 2x10, 4x8 ASx28 and ASx36 coming Streaming = Large Block Sequential LSI Logic Confidential © LSI Logic 2003

SATA Multiplier vs SAS Expander SATA HDD SAS HDD 1 1 2 2 3 SATA HDD = 3 4 5 SATA Multiplier Single Host Connection Different chips for different HDD Counts Vitesse 1x15 Silicon Image 1 x 5 SAS Expander X1, x2, x3, x4 Host Connection ASx12 is 1x11, 2x10, 4x8 ASx28 and ASx36 coming LSI Logic, PMC Sierra, Vitesse SATA Controller SAS Controller Note: ALL SATA FUNCTIONALITY IS CONTAINED WITHIN SAS Except: SAS cannot talk to SATA multipliers LSI Logic Confidential © LSI Logic 2003

Typical Configurations Sample Configurations-Better than SCSI ^Clustered Solution < Cascaded JBODs LSI Logic Confidential © LSI Logic 2003

Standards & Initiatives SAS Ecosystem LSI LOGIC First Article Production LSISAS1064 LSISAS1068 Controller Hardware Expanders LSISASx12 Vendor A Vendor B Vendor C Vendor D Hard Drives SAS x1 SAS x4 Cables + Connectors HBAs RAID Controllers Boards Protocol Analyzers Bus Exercisers Jitter/Phy Analysis Validation Equipment Standards & Initiatives SAS v1.0 Spec STA Plug-Fest Letter Ballot INCITS Approved Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 2003 2004 2005 3/10/2004 LSI Confidential – Internal Use Only LSI Logic Confidential © LSI Logic 2003

It’s REAL!! Learn About System Bandwidth LSI Logic Confidential © LSI Logic 2003

The SAS Infrastructure

External 4X Connector LSI Logic Confidential © LSI Logic 2003

SAS / SATA Multi-Lane Internal & SAS Multi-Lane External (Drawing courtesy of Molex) LSI Logic Confidential © LSI Logic 2003

SAS Multi-Lane Connections (Drawing courtesy of Molex) LSI Logic Confidential © LSI Logic 2003

New Connectors have been defined: SFF 8087 Internal SAS Connector LSI Logic Confidential © LSI Logic 2003

SFF 8088 External SAS Connector LSI Logic Confidential © LSI Logic 2003

SFF 8088 External SAS Connector LSI Logic Confidential © LSI Logic 2003

Pieces of the puzzle Cables Chassis Technical Cable Concepts, Inc. 350 Lear Avenue, Costa Mesa, CA 92626 Casey Dugan (714) 835-1081 x135 (caseyd@techcable.com) www.techcable.com Chassis AIC LSI Logic Confidential © LSI Logic 2003

Backup

SCSI - What If?? SCSI HDDs ( 1-15 HDD) LSI Logic Confidential © LSI Logic 2003

Calculating System Bandwidth ~ 480 MB/s OR ~1000+ IOPS 4 SAS @ 300MB/s 1200MB/s Large Block Sequential HDD ~ 60MB/s 8 HDD = 480MB/s Small Block Random HDD ~ 120 IOPs &HDD Cache 8HDD ~ >1000 IOPs PCIX 64b, 133MHz ~1000MB/s PCIe ~ 250MB/lane X4, X8, X16 common 8 SAS @ 300MB/s 2400MB/s LSI Logic Confidential © LSI Logic 2003

SAS Protocols SSP - Serial SCSI Protocol Used whenever SAS HDD talks to SAS Controller (with or without SAS Expanders) SATA Always used to communicate with a SATA HDD STP - SATA Tunneled Protocol Used when SATA HDD is connected to SAS controller via SAS expander STP is used between SAS controller and SAS expander; SATA is used to talk to the SATA HDD STP EMB (Enclosure Management Bridge), Allows a SAS controller to talk to the I2C interface embedded in the x12 Expander. Typically the I2C interface is connected to an external Enclosure Management Processor SMP - Serial Management Protocol Allows SAS controllers to configure SAS expanders LSI Logic Confidential © LSI Logic 2003

Serial Protocols SSP STP SMP SSP or SMP EMB SSP I2C bus SATA SATA LSI1068 SSP STP SSP SMP or SMP EMB LSIx12 LSIx12 SSP I2C bus SATA SATA SAS HDD SAS HDD SATA HDD SATA HDD Enc. Proc. LSI Logic Confidential © LSI Logic 2003