Trends in Storage Subsystem Technologies

Trends in Storage Trends in Storage Subsystem TechnologiesSubsystem Technologies

Michael Joyce, Senior Director Michael Joyce, Senior Director

Mylex & OEM Storage SubsystemsMylex & OEM Storage Subsystems

IBMIBM

The Drive Interface The Drive Interface ProgressionProgression

1996 1998 2000 2002 2004

Ultra640SCSI

640 MB/s

UltraSCSI

Ultra2SCSI

Ultra160SCSI

Ultra320SCSI

40 MB/s 80 MB/s 160 MB/s 320 MB/s

Parallel SCSI

Fibre Channel Arbitrated Loop

640 MB/s

UltraSCSI

Ultra2SCSI

Ultra160SCSI

Ultra320SCSI

40 MB/s 80 MB/s

100 MB/s

320 MB/s

200 MB/s 400 MB/s

System Interface System Interface ProgressionProgression

1996 1998 2000 2002 2004

533 MB/s 2 GB/s133 MB/s 266 MB/s 1 GB/s

PCI/ PCI-X

32-bit33 MHz

64-bit33 MHz

64-bit66 MHz

64-bit133 MHz

64-bit266 MHz

Fibre Channel

1 Gb/s 2 Gb/s 10 Gb/s

Multi-Node SANMulti-Node SANN-Node, Switched Fibre, N-RAID Controllers, N-Node, Switched Fibre, N-RAID Controllers,

FC Switch

RAID Ctlr

Port 0 Port 1

RAID Ctlr

Port 0 Port 1

FC HBA

RAID Ctlr

Port 0 Port 1

RAID Ctlr

Port 0 Port 1

FC HBAFC HBA

FC HBA

Early IB Deployment:Early IB Deployment:First-order Network FocusFirst-order Network Focus

CharacteristicsCharacteristics IB used mainly to get I/O out of 1U front-IB used mainly to get I/O out of 1U front-

end servers.end servers. High-end servers may not have IB linksHigh-end servers may not have IB links SANs and LANs co-exist with IBSANs and LANs co-exist with IB IB-to-FC and IB-to-Ethernet bridges to IB-to-FC and IB-to-Ethernet bridges to

interconnect IB to SANs and LANsinterconnect IB to SANs and LANs

...

Front-end/ Web Servers

High-end Servers

RAID Subsystems

IB Switch

Internet

LAN

FC SAN

Initial iSCSI DeploymentInitial iSCSI Deployment

Until security and traffic/ usage perceptions are overcome, iSCSI SANsand LANs/ WANs will be distinct networks.

Storage Arrays

Server Nodes

FC SAN

Storage Arrays

Server Nodes

FC SAN

Storage Arrays

Server Nodes

iSCSI

IP Network

Trend Towards Fabric Trend Towards Fabric InterconnectsInterconnects

““Get off the Bus - Get on the Fabric!”Get off the Bus - Get on the Fabric!” Gigabit speeds and shrinking device Gigabit speeds and shrinking device

geometries make it difficult to sustain geometries make it difficult to sustain buses.buses.– Point-to-point interconnects gaining ground.Point-to-point interconnects gaining ground.

Within storage controllers, the current Within storage controllers, the current interconnect continues to be PCI/ PCI-Xinterconnect continues to be PCI/ PCI-X

But, competing technologies are But, competing technologies are appearing ...appearing ...– RapidIO, HyperTransport™ (AMD), 3GIO (Intel) RapidIO, HyperTransport™ (AMD), 3GIO (Intel)

Divergence in Divergence in Interconnect TechnologiesInterconnect Technologies

Historically, storage subsystems have Historically, storage subsystems have presented disk-drive like interfaces to presented disk-drive like interfaces to the host.the host.– SCSI, Fibre ChannelSCSI, Fibre Channel

Moving forward, system interconnects Moving forward, system interconnects are becoming fabric oriented to address are becoming fabric oriented to address distance, reliability, manageability and distance, reliability, manageability and other issues.other issues.– InfiniBand, iSCSI, 10 Gb Fibre ChannelInfiniBand, iSCSI, 10 Gb Fibre Channel

… … DivergenceDivergence

On next Fibre Channel progression, On next Fibre Channel progression, interfaces diverge.interfaces diverge.– 10 Gb for system, 4 Gb for drives10 Gb for system, 4 Gb for drives

Serial ATA emerges as a viable drive Serial ATA emerges as a viable drive interface for desktops and storage interface for desktops and storage subsystems.subsystems.

RAID/ Storage controllers facilitate divergence between system and drive interfaces.

Local Bus)

Peripheral B

us

CPUCore

RAIDLogic

StorageProtocol

I/FBridge UART

I2C

GPIO

GPTPCI-XI/F

… … Lead to Integrated RAIDLead to Integrated RAID

RAID TeamingRAID TeamingDual or Multiple PCI RAID Controllers plugged in Dual or Multiple PCI RAID Controllers plugged in

the same system, share the same backend the same system, share the same backend disk devices (through SCSI or FC drive disk devices (through SCSI or FC drive enclosure(s)). enclosure(s)).

Mylex

Mylex

Mylex

Mylex

Terminator Switch (SCSI) or FC Hub

Disk Drives (JBOD)Dual ported Enclosure (SCSI or FC)

Dual PCI RAID Controllers

Host System

FlashCopyFlashCopy

Background Copy

Write

Write

Read

Read

Source Logical Drive Target Logical Drive

Remote MirroringRemote Mirroring

Fibre Channel Switch local

storagecontroller

"remote"storagecontroller

WRITE

WRITE

READ

Establish: bulk copyMaintain: replicate writesFailover to remote copy

Data SiphonData Siphon

Fibre Channel Switch NEW

storagesubsystem

LEGACYstoragesubsystem

Goal: replace legacy subsystem with new subsystem seamlesslyFetch from legacy subsystem in "chunks" on demand Write to new subsystemSignal when old subsystem is "empty"

WRITE

READ

READ

In SummaryIn Summary Serial ATA emerges as a common interface Serial ATA emerges as a common interface

for desktop and server class drives.for desktop and server class drives. System interconnects move towards iSCSI System interconnects move towards iSCSI

and InfiniBand with iSCSI appearing to be and InfiniBand with iSCSI appearing to be gaining momentum.gaining momentum.

System-on-chip trends will drive towards System-on-chip trends will drive towards integrated RAID devices, especially at the integrated RAID devices, especially at the low end.low end.

RAID functionality enhancements will RAID functionality enhancements will continue providing increased data continue providing increased data availability, mobility, and manageabilityavailability, mobility, and manageability