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Solving the IO Bottleneck in NextGen DataCenters ... - IMEX Research

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<strong>IMEX</strong><br />

RESEARCH.COM<br />

<strong>Solv<strong>in</strong>g</strong> <strong>the</strong> <strong>IO</strong> <strong>Bottleneck</strong><br />

<strong>in</strong> <strong>NextGen</strong> <strong>DataCenters</strong> &<br />

Cloud Comput<strong>in</strong>g<br />

Are SSDs Ready for Enterprise Storage Systems<br />

Anil Vasudeva, President & Chief Analyst, <strong>IMEX</strong> <strong>Research</strong><br />

© 2007-11 <strong>IMEX</strong> <strong>Research</strong><br />

All Rights Reserved<br />

Copy<strong>in</strong>g Prohibited<br />

Please write to <strong>IMEX</strong> for authorization<br />

Anil Vasudeva<br />

President & Chief Analyst<br />

imex@imexresearch.com<br />

408-268-0800<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


Abstract<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

<strong>Solv<strong>in</strong>g</strong> <strong>the</strong> I/O <strong>Bottleneck</strong> <strong>in</strong> <strong>NextGen</strong> Data Centers & Cloud Comput<strong>in</strong>g<br />

Virtualization br<strong>in</strong>gs tremendous advantages to data centers of all sizes – large and<br />

small. But <strong>the</strong> rapid proliferation of virtual mach<strong>in</strong>es (VMs) per physical server, <strong>in</strong> its<br />

wake, creates a highly randomized I/O problem, rais<strong>in</strong>g performance bottlenecks. To<br />

address this I/O issue, <strong>the</strong> IT <strong>in</strong>dustry and storage adm<strong>in</strong>istrators <strong>in</strong> particular, have<br />

begun <strong>the</strong> adoption of a slew of newer technology solutions - rang<strong>in</strong>g from faster and<br />

larger memories <strong>in</strong> cache, SSDs for higher <strong>IO</strong>PS cost effectively, high bandwidth<br />

(10GbE) networks us<strong>in</strong>g NPIVs for virtualized networks between VMs and shared<br />

storage systems along with embedded <strong>in</strong>telligence software to optimize various VM<br />

workloads – all <strong>in</strong> order to meet various SLA metrics of performance, availability, cost<br />

etc..<br />

Are you aware of <strong>the</strong> side-effects that get created from Server Virtualization and<br />

prepared to ask pert<strong>in</strong>ent questions of your suppliers of IT Infrastructure Equipment,<br />

Storage Virtualization and Data Storage Management software as well as <strong>in</strong> <strong>the</strong>ir<br />

implementation to achieve targeted results <strong>in</strong> performance, availability, scalability,<br />

<strong>in</strong>teroperability and data management <strong>in</strong> <strong>the</strong>ir virtualized data centers<br />

This presentation provides an illustrative view of <strong>the</strong> impact of Server Virtualization on<br />

exist<strong>in</strong>g storage I/O solutions and best practices. It del<strong>in</strong>eates <strong>the</strong> roles, capabilities and<br />

cost effectiveness of emerg<strong>in</strong>g technologies <strong>in</strong> mitigat<strong>in</strong>g <strong>the</strong> I/O bottlenecks so <strong>the</strong> IT<br />

<strong>in</strong>frastructure implementers can achieve <strong>the</strong>ir targeted performance under various<br />

workloads, from <strong>the</strong>ir storage systems <strong>in</strong> virtualized data centers.<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.<br />

2


Agenda<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

• Data Centers & Cloud Infrastructure<br />

• Cloud Comput<strong>in</strong>g Architecture<br />

• Performance Metrics by Workload<br />

• Anatomy of Data Access<br />

• Data Center Performance <strong>Bottleneck</strong>s<br />

• Improv<strong>in</strong>g Query Response Time <strong>in</strong> OLTP<br />

• Role of SSD <strong>in</strong> Improv<strong>in</strong>g I/O Perf. Gap<br />

• SCM: A New Storage Class Memory SSDs<br />

• Price Erosion & <strong>IO</strong>PS/GB<br />

• Choos<strong>in</strong>g SSD vs. Memory to Improve TPS<br />

• New Storage Usage Hierarchy <strong>in</strong> NGDC & Clouds<br />

• <strong>IO</strong> <strong>Bottleneck</strong> Mitigation <strong>in</strong> Virtualized Servers<br />

• I/O Forensics for Auto Storage-Tier<strong>in</strong>g<br />

• Apps Benefitt<strong>in</strong>g from Improved I/O<br />

• Key Takeaways<br />

• Acknowledgements<br />

3<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


Data Centers & Cloud Infrastructure<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

Public CloudCenter©<br />

Enterprise VZ Data Center<br />

On-Premise Cloud<br />

Vertical<br />

Clouds<br />

IaaS, PaaS<br />

SaaS<br />

Servers<br />

VPN<br />

Switches: Layer 4-7,<br />

Layer 2, 10GbE, FC Stg<br />

Supplier/Partners<br />

Remote/Branch Office<br />

Cellular<br />

Wireless<br />

ISP<br />

ISP<br />

ISP<br />

ISP<br />

Internet<br />

Core<br />

Optical<br />

Edge<br />

ISP<br />

Web 2.0<br />

Social Ntwks.<br />

Facebook,<br />

Twitter, YouTube…<br />

Cable/DSL…<br />

ISP<br />

Home Networks<br />

ISP<br />

Cach<strong>in</strong>g, Proxy,<br />

FW, SSL, IDS, DNS,<br />

LB, Web Servers<br />

Tier-1<br />

Edge Apps<br />

Application Servers<br />

HA, File/Pr<strong>in</strong>t, ERP,<br />

SCM, CRM Servers<br />

FC/ IPSANs<br />

Database Servers,<br />

Middleware, Data<br />

Mgmt<br />

Tier-3<br />

Data Base<br />

Servers<br />

Tier-2 Apps<br />

Directory Security Policy Management<br />

Middleware Platform<br />

Source:: <strong>IMEX</strong> <strong>Research</strong> - Cloud Infrastructure Report © 2009-11<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.<br />

4


IT Industry’s Journey - Roadmap<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

SIVAC<br />

®<strong>IMEX</strong><br />

Cloudization<br />

Integration/Consolidation<br />

On-Premises > Private Clouds > Public Clouds<br />

DC to Cloud-Aware Infrast. & Apps. Cascade migration to SPs/Public Clouds.<br />

Integrate Physical Infrast./Blades to meet CAPSIMS ®<strong>IMEX</strong><br />

Cost, Availability, Performance, Scalability, Inter-operability, Manageability & Security<br />

Standardization<br />

Automation<br />

Automatically Ma<strong>in</strong>ta<strong>in</strong>s Application SLAs<br />

(Self-Configuration, Self-Heal<strong>in</strong>g ©<strong>IMEX</strong> , Self-Acctg. Charges etc)<br />

Virtualization<br />

Pools Resources. Provisions, Optimizes, Monitors<br />

Shuffles Resources to optimize Delivery of various Bus<strong>in</strong>ess Services<br />

Standard IT Infrastructure- Volume Economics HW/Syst SW<br />

(Servers, Storage, Network<strong>in</strong>g Devices, System Software (OS, MW & Data Mgmt SW)<br />

Source:: <strong>IMEX</strong> <strong>Research</strong> - Cloud Infrastructure Report © 2009-11<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.<br />

5


Cloud Comput<strong>in</strong>g Architecture<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

Private Cloud<br />

Enterprise<br />

Cloud Comput<strong>in</strong>g<br />

Hybrid<br />

Cloud<br />

Public Cloud Service<br />

Providers<br />

SaaS Applications<br />

SaaS<br />

App<br />

SLA<br />

App<br />

SLA<br />

App<br />

SLA<br />

App<br />

SLA<br />

App<br />

SLA<br />

PaaS<br />

EJB<br />

Ruby<br />

Platform Tools & Services<br />

Python<br />

.Net<br />

PHP<br />

Operat<strong>in</strong>g Systems<br />

…..<br />

…..<br />

Management<br />

IaaS<br />

Virtualization<br />

Resources (Servers, Storage, Networks)<br />

Application’s SLA dictates <strong>the</strong> Resources Required to meet specific<br />

requirements of Availability, Performance, Cost, Security, Manageability etc.<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


Performance Metrics by Workload<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

<strong>IO</strong>PS* (*Latency-1)<br />

1000 K<br />

100 K<br />

10K<br />

1K<br />

100<br />

Transaction<br />

Process<strong>in</strong>g<br />

(RAID - 1, 5, 6)<br />

TP<br />

OLTP<br />

eCommerce<br />

Data<br />

Warehous<strong>in</strong>g<br />

HPC<br />

Bus<strong>in</strong>ess<br />

Intelligence<br />

OLAP<br />

Scientific Comput<strong>in</strong>g<br />

Imag<strong>in</strong>g<br />

Audio<br />

Video<br />

(RAID - 0, 3)<br />

HPC<br />

Web 2.0<br />

10<br />

1 5<br />

10<br />

50<br />

*<strong>IO</strong>PS for a required response time ( ms)<br />

*=(#Channels*Latency-1)<br />

100<br />

MB/sec<br />

500<br />

Source:: <strong>IMEX</strong> <strong>Research</strong> - Cloud Infrastructure Report © 2009-11<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


Anatomy of Data Access<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

Performance<br />

Server<br />

Processor<br />

Disk I/O<br />

I/O<br />

Gap<br />

For <strong>the</strong> time it takes to do each<br />

Disk Operation:<br />

- Millions of CPU Operations can be done<br />

- Hundreds of Thousands of Memory Operations<br />

can be accomplished<br />

1980 1990 2000 2010<br />

Anatomy of<br />

Data Access<br />

Time taken by CPU,<br />

Memory, Network, Disk<br />

for a typical I/O<br />

Operation dur<strong>in</strong>g a<br />

Data Access<br />

A 7.2K/15k rpm HDD can do 100/140 <strong>IO</strong>PS<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


Data Center Performance <strong>Bottleneck</strong>s<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

Applications<br />

Excessive Lock<strong>in</strong>g<br />

Data Contention<br />

I/O Delays/Errors<br />

Network I/O<br />

Network Congestion<br />

Dropped packets<br />

Data Retransmissions<br />

Timeouts<br />

Component Failures<br />

Storage I/O Connect<br />

Lack of Bandwidth<br />

Overloaded PCIe Connect<br />

Storage Device Contention<br />

LAN Access Networks<br />

Storage I/O Access<br />

Clients<br />

W<strong>in</strong>dows,<br />

L<strong>in</strong>ux, Unix<br />

Servers<br />

Web Servers<br />

Application Servers<br />

Database Servers<br />

Storage<br />

Web, Application,<br />

Database<br />

User <strong>Bottleneck</strong>s<br />

Connectivity Timeouts,<br />

Workload Surges<br />

Server <strong>Bottleneck</strong>s<br />

Lack of Srvr Power<br />

<strong>IO</strong> Wait & Queu<strong>in</strong>g CPU<br />

Overhead I/O Timeouts<br />

Device <strong>Bottleneck</strong>s<br />

Device I/O Hotspots<br />

Cache Flush<br />

Lack of Storage Capacity<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


Improv<strong>in</strong>g Query Response Time <strong>in</strong> OLTP<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

Query Response Time (ms)<br />

0<br />

8<br />

6<br />

4<br />

2<br />

HDDs<br />

14 Drives<br />

$$<br />

HDDs<br />

112 Drives<br />

w short<br />

strok<strong>in</strong>g<br />

$$$$$$$$<br />

Hybrid<br />

HDDs<br />

36 Drives<br />

+ SSDs<br />

$$$$<br />

SSDs<br />

12 Drives<br />

• Improv<strong>in</strong>g Query Response Time<br />

• Cost effective way to improve Query response time for a given number<br />

of users or servic<strong>in</strong>g an <strong>in</strong>creased number of users at a given response<br />

time is best served with use of SSDs or Hybrid (SSD + HDDs)<br />

approach, particularly for Database and Onl<strong>in</strong>e Transaction Applications<br />

$$$<br />

Conceptual Only -Not to Scale<br />

0 10,000 20,000 30,000<br />

40,000<br />

<strong>IO</strong>PS (or Number of Concurrent Users)<br />

Source: <strong>IMEX</strong> <strong>Research</strong> SSD Industry Report © 2011<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.<br />

10


Role of SSD <strong>in</strong> Improv<strong>in</strong>g I/O Perf. Gap<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

Price<br />

$/GB<br />

NAND<br />

NOR<br />

SCM<br />

DRAM<br />

CPU<br />

SDRAM<br />

PCIe<br />

SSD<br />

DRAM gett<strong>in</strong>g<br />

Faster (to feed faster CPUs) &<br />

Larger (to feed Multi-cores &<br />

Multi-VMs from Virtualization)<br />

Servers<br />

Tape<br />

HDD<br />

SATA<br />

SSD<br />

Hybr. Storage<br />

HDD becom<strong>in</strong>g<br />

Cheaper, not faster<br />

SSD segment<strong>in</strong>g <strong>in</strong>to<br />

• PCIe SSD Cache<br />

- as backend to DRAM &<br />

• SATA SSD<br />

- as front end to HDD<br />

Source: <strong>IMEX</strong> <strong>Research</strong> SSD Industry Report © 2011<br />

Performance<br />

I/O Access Latency<br />

11<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


• Performance<br />

• Data<br />

• Reliability<br />

• -<br />

• Environment<br />

• Volumetric<br />

• Resistance<br />

SCM: A New Storage Class Memory<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

• SCM (Storage Class Memory)<br />

Solid State Memory fill<strong>in</strong>g <strong>the</strong> gap between DRAMs & HDDs<br />

Marketplace segment<strong>in</strong>g SCMs <strong>in</strong>to SATA and PCIe based SSDs<br />

• Key Metrics Required of Storage Class Memories<br />

Device - Capacity (GB), Cost ($/GB),<br />

- Latency (Random/Block RW Access-ms); Bandwidth<br />

BW(R/W- GB/sec)<br />

Integrity - BER (Better than 1 <strong>in</strong> 10^17)<br />

- Write Endurance (30K PE Cycles No. of writes before<br />

death);<br />

Data Retention (5 Years); MTBF (2 millions of Hrs),<br />

- Power Consumption (Watts);<br />

Density (TB/cu.<strong>in</strong>.); Power On/Off Time<br />

(sec),<br />

- Shock/Vibration (g-force); Temp./Voltage Extremes<br />

4-Corner (oC,V); Radiation (Rad)<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.<br />

12


SSDs - Price Erosion & <strong>IO</strong>PS/GB<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

600<br />

8<br />

HDD<br />

<strong>IO</strong>PS/GB SSDs<br />

<strong>IO</strong>PS/GB<br />

300<br />

SSD<br />

SSD Units (M)<br />

Enterprise HDD Units (M)<br />

4<br />

Units (Millions)<br />

0<br />

<strong>IO</strong>PS/GB HDDs<br />

2009 2010 2011 2012 2013 2014<br />

Note: 2U storage rack, • 2.5” HDD max cap = 400GB / 24 HDDs, de-stroked to 20%, • 2.5” SSD max cap = 800GB / 36 SSDs<br />

0<br />

Source: <strong>IMEX</strong> <strong>Research</strong> SSD Industry Report © 2011<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


Choos<strong>in</strong>g SSD vs. Memory to Improve TPS<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

2500<br />

2000<br />

1500<br />

TPS<br />

1000<br />

2.5 x<br />

4.0 x<br />

SSD PCIe<br />

500<br />

0<br />

4.0 x<br />

SSD SATA<br />

2.5 x<br />

0 2 4 6 8 10 12 14 16 18 20<br />

Buffer Pool (Memory) GB<br />

HDD RAID 10<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


Data Storage Usage Patterns –<br />

Data Access vs. Age of Data<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

80% of <strong>IO</strong>Ps<br />

80% of TB<br />

Data Access<br />

Performance<br />

Data Protection<br />

Scale<br />

Cost<br />

Data Reduction<br />

Storage Growth<br />

SSDs<br />

1 Day 1 Week 1 Month 2 Mo. 3 Mo. 6 Mo.<br />

1 Year<br />

2 Yrs<br />

Age of Data<br />

Source:: <strong>IMEX</strong> <strong>Research</strong> - Cloud Infrastructure Report © 2009-11<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


New Storage Hierarchy <strong>in</strong> NGDC &<br />

Clouds<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

I/O Access Frequency vs. Percent of Corporate Data<br />

95%<br />

75%<br />

65%<br />

% of I/O Accesses<br />

SSD<br />

• Logs<br />

• Journals<br />

• Temp Tables<br />

• Hot Tables<br />

FCoE/<br />

SAS<br />

Arrays<br />

• Tables<br />

• Indices<br />

• Hot Data<br />

Cloud<br />

Storage<br />

SATA<br />

• Back Up Data<br />

• Archived Data<br />

• Offsite DataVault<br />

1%<br />

2% 10% 50% 100%<br />

% of Corporate Data<br />

Source:: <strong>IMEX</strong> <strong>Research</strong> - Cloud Infrastructure Report © 2009-11<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.<br />

16


<strong>IO</strong> <strong>Bottleneck</strong> Mitigation <strong>in</strong> Virtualized<br />

Servers<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

vSphere ESX<br />

VM Client 1<br />

VM Client 2<br />

VM Client n<br />

XCL<br />

Mgr.<br />

I/O<br />

Reg.<br />

XCL<br />

Driver<br />

I/O<br />

Reg.<br />

XCL<br />

Driver<br />

I/O<br />

Reg.<br />

XCL<br />

Driver<br />

Disk<br />

Controller.<br />

XCL<br />

VLUN<br />

SSD<br />

Driver<br />

ESX Kernel<br />

Primary<br />

Storage<br />

Offload<strong>in</strong>g <strong>IO</strong>PS from<br />

Primary Storage<br />

Both Applications &<br />

Storage Run Faster<br />

SSD Drive<br />

w/ESX Driver<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


I/O Forensics for Auto Storage-Tier<strong>in</strong>g<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

Storage-Tiered Virtualization<br />

Storage-Tier<strong>in</strong>g at LBA/Sub-LUN Level<br />

Physical Storage Logical Volume<br />

SSDs<br />

Arrays<br />

Hot Data<br />

HDDs<br />

Arrays<br />

Cold Data<br />

LBA Monitor<strong>in</strong>g and Tiered Placement<br />

• Every workload has unique I/O access signature<br />

• Historical performance data for a LUN can identify<br />

performance skews & hot data regions by LBAs<br />

Source: IBM & <strong>IMEX</strong> <strong>Research</strong> SSD Industry Report 2011 ©<strong>IMEX</strong> 2010-11<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.<br />

18


Apps Benefitt<strong>in</strong>g from Improved I/O<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

Smart Mobile<br />

Devices<br />

Commercial<br />

Visualization<br />

Bio<strong>in</strong>formatics<br />

& Diagnostics<br />

Decision Support<br />

Bus. Intelligence<br />

Enterta<strong>in</strong>ment-<br />

VoD / U-Tube<br />

Data: <strong>IMEX</strong> <strong>Research</strong> & Panasas<br />

19<br />

Instant On Boot Ups<br />

Rugged, Low Power<br />

1GB/s, __ms<br />

Render<strong>in</strong>g (Texture & Polygons)<br />

Very Read Intensive, Small Block I/O<br />

Data Warehous<strong>in</strong>g<br />

Random <strong>IO</strong>, High OLTPM<br />

Most Accessed Videos<br />

Very Read Intensive<br />

10 GB/s, __ms 1GB/s, __ms<br />

4 GB/s, __ms<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.


Key Takeaways<br />

<strong>IMEX</strong><br />

RESEARCH.COM<br />

• <strong>Solv<strong>in</strong>g</strong> I/O Problems<br />

• I/O <strong>Bottleneck</strong>s occur at multiple places <strong>in</strong> <strong>the</strong> Compute Stack, <strong>the</strong> largest<br />

be<strong>in</strong>g at Storage I/O<br />

• SSD comes out cheaper/<strong>IO</strong>P for <strong>IO</strong> Intensive Apps<br />

• To get of Reads – Improve Index<strong>in</strong>g, archive out old data<br />

• M<strong>in</strong>imize <strong>the</strong> impact of writes – Get rid of temp tables/filesorts on slow<br />

disks.<br />

• Compress big varchar/text/blobs<br />

• Data Forensics and Tiered Placement<br />

• Every workload has unique I/O access signature<br />

• Historical performance data for a LUN can identify performance skews &<br />

hot data regions by LBAs<br />

• Use Smart Tier<strong>in</strong>g to identify hot LBA regions and non-disruptively migrate<br />

hot data from HDD to SSDs.<br />

• Typically 4-8% of data becomes a candidate and when migrated to SSDs<br />

can provide response time reduction of ~65% at peak loads<br />

© 2010‐11 <strong>IMEX</strong> <strong>Research</strong>, Copy<strong>in</strong>g prohibited. All rights reserved.

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