SSD To Solve The I/O Bottleneck

Iri TrashanskiDirector, Business DevelopmentSanDisk

What Is A Solid State Drive?A Solid State Drive (SSD) is a data storage device

that uses flash media to store data, instead of the spinning platters found in mechanical hard disk drives

SSD BenefitsReliability and DurabilityMobilityPerformanceImproved user experience

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Gartner, Jo UnsworthDecember, 2006

When Random and SequentialAre Used? Random

OS changes and updatesA single DLL is generally 5 to 6 Disk Locations (min)

Directory, MFT Entry, and other File System MetadataPE Hdr page, .text pages, .data pages, .rsrc pages, etc.

Applications and documents changes and updates (on-the-go)Access user data

SequentialBootHibernateApplication load (main file)

For example:When opening an application, the data files will be read in a sequential manner, however, all the associated DLL’s (~100 in average) will be read and loaded in random from 5-6 disk locations per DLL.

HDD Performance Is Not About Transfer Rate But IOPS! HDD transfer time = Interface transfer + media

transfer + mechanical latency (in ms!)For a typical 4KB request, the mechanical impact at the HDD level accounts for ~95% of the entire transfer!Transfer time accounts for a fraction of actual disk access time

Operating System (OS) transfersRandom readSequential readRandom writeSequential write

Random read operations accounts for more than 50% of the OS transfers

Major effect on machine behavior

4KB Read is 50% of the read transfers

Microsft VISTA Read data

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HDD vs. SSDSeek and Latency

Average Access Time = Ave. Seek Time + Latency Time/2Average Access Time = 12 msec + 5 msec ~ 17 msec (5400rpm)

Seek

Latency

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Access time is fixed to 0.11ms

HDD Versus SSDModel SSD HDD SATA 2.5’

80GBTransfer Rate:Interface rate 150 MB/s 150 MB/sMaximum Internal* R : 67 MB/sec*

W: 47 MB/sec*R : 28 – 44 MB/sec*W: 28 – 44 MB/sec*

IOPS 512B transfer size**R: 7430

512B transfer size**R: 68

IOPS 4KB transfer size**R: 5405

4KB transfer size**R: 67

Read Seek Time:Track-to-track 0.11ms* 3ms*Average 0.11ms* 17ms*Maximum 0.15ms* 33ms*

7* Based on H2BENCHW 3.6** Based on IOMETER 2003.12.16

SSD vs. HDD IOPS

5405.808215

1019.654617

7430.133983

53.91374467.09958667.5666460

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0.5 1 2 4 8 16 32 64 128 256 512 1024Transfer Size

IOPS

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SATA 7200 RPM

x80

Based on IOMETER 2003.12.16

Conducted on Dell Latitude D420/D620 notebook

User Scenario Benchmarks

PC Mark 05

4.5

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2.7

20.9

6.1

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32.1

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XP Startup

Application Loading

General Usage

Virus Scan

MB/s

SSD

2.5 HDD

1.8 HDD

10 sec 20 sec 30 sec

SSD 19HDD

* HDD - 4200RPM, 60GB, 1.8”** SSD - SanDisk SSD UATA 1.8”

25

SSD 17HDD 27SSDHDD

SSDHDD

3.25.1

4.38.2

S4 - Resume

Shut down

2MB PDF

4MB PPT

10 sec 20 sec 30 sec 40 sec 50 sec 60 sec 70 sec

Total: 65 Sec

BIOS OS boot Applications

11 Sec 37 Sec 17 Sec

10 Sec Total: 31 Sec12 Sec 9 Sec

Total: 50 Sec11 Sec 22 Sec 17 Sec

Total: 39 Sec10 Sec 20 Sec 9 Sec

XP Experience

Vista Experience

* HDD - SATA, 5400RPM, 80GB ** SSD - SanDisk SSD SATA 5000 2.5”

HDD*

SSD**

HDD*

SSD**

SSD Bootdemo

SSD Bootdemo

MLC Meets PC Market Requirements

Double Density

HighPerformance

HighEndurance

Binary MLCBinaryBinary MLCMLC

Lower price pointHigh performance

Random ReadMinimal degradation80x better than HDD

Endurance Supporting user scenarios Exceed PC OEM requirements Unlimited read

Field proven – mobile handsets and CE devices

Binary MLCBinaryBinary MLC

Binary MLCBinaryBinary MLCMLC

Thank You !