Roadmap to Membership of RICS - Pathways and Routes
ISR UNIT2.ppt
1.
2. Disk Drive Components, Disk Drive
Performance, Host Access to Data, Direct-
Attached Storage , Storage Design Based on
Application Requirements and Disk
Performance, Disk Native Command Queuing,
Introduction to Flash Drives.
Concept in Practice: VMware ESXi.
Storage System Environment - 2
15. Key points covered in this lesson:
Physical drives are made up of:
◦ HDA
Platters connected via a spindle
Read/write heads which are positioned by an actuator
◦ Controller
Controls power, communication, positioning, and
optimization
Data is structured on a drive using tracks,
sectors, and cylinders
The geometry of a disk impacts how data is
recorded on a platter
Physical Disks
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16. Disk Drive Performance
Logical Components
Storage System Environment
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17. Upon completion of this lesson, you will be
able to:
Describe the factors that impact the
performance of a drive
Describe how drive reliability is measured
Physical Disks
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18. Seek time is the time for
read/write heads to move
between tracks
Seek time specifications
include:
◦ Full stroke
◦ Average
◦ Track-to-track
Physical Disks
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22. Mean Time Between Failure
Amount of time that one can anticipate a
device to work before an incapacitating
malfunction occurs
◦ Based on averages
◦ Measured in hours
Determined by artificially aging the product
Physical Disks
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23. Consider a disk I/O system in which an I/O request arrives
at a rate of 100 I/Os per second. The service time, RS, is 4
ms.
◦ Utilization of I/O controller (U=a × Rs)
◦ Total response time (R=Rs /1-U)
Calculate the same with service time is doubled
Storage System Environment
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0% 100%
Utilization
Knee of curve: disks at
about 70% utilization
Low Queue Size
70%
24. Conventional disk drive
Mechanical Delay associated
with conventional drive
◦ Seek time
◦ Rotational latency
More power consumption
due to mechanical operations
Low Mean Time Between
Failure
Enterprise flash drive
Highest possible throughput
per drive
◦ No Spinning magnetic media
◦ No Mechanical movement
which causes seek and latency
◦ Solid State enables consistent
I/O performance
Very low latency per I/O
Energy efficient storage
design
◦ Lower power requirement per
GB of storage
◦ Lower power requirement per
IOPS
Storage System Environment
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25. Drive is based on Flash Solid State memory
technology
◦ High performance and low latency
◦ Non volatile memory
◦ Uses single layer cell (SLC) or Multi Level cell (MLC) to
store data
Enterprise Flash Drives use a 4Gb FC interface
Storage System Environment
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26. Faster performance
◦ Up to 30 times greater
IOPS (benchmarked)
◦ Typical applications: 8 –
12X
◦ Less than 1 millisecond
service time
More energy efficient
◦ 38 percent less per
terabyte
◦ 98 percent less per IO
Better reliability
◦ No moving parts
◦ Faster RAID rebuilds Storage System Environment
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IO per second
Response
Time
1 Flash drive
1@15K
Fibre
Channel
drive
10@15K
Fibre
Channel
drives
30@15K
Fibre
Channel
drives
27. Position Enterprise Flash Drives as the high-
performance option in demanding
environments
◦ Low latency applications, also known as “Tier-
0” applications
Standard form-factor and capacity design
allows for easier integration
High performance, low power for a “Green”
initiative
Target Customer/Market Segments:
◦ High performance solutions coupled with low power
◦ Specifically target Oracle database customers
initially
◦ Financial trading Storage System Environment
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28. Key points covered in this lesson:
Disk drive components and geometry
Disk drive addressing scheme
Disk drive performance
Convention drive Vs Enterprise Flash Drives
Enterprise Flash Drives for high performance
and low power storage solution
Storage System Environment
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29. Key points covered in this chapter:
Storage system environment components:
◦ Host, connectivity and storage
Physical disk structure and addressing
Factors affecting disk performance
Flash drives benefits
Storage System Environment
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30. What are some examples of hosts?
What are the physical and logical components
of a host?
What are the common connectivity protocols
used in computing environments?
What is the difference between seek time and
rotational latency?
What is the difference between internal and
external data transfer rates?
Storage System Environment
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