The document presents information about solid state drives (SSDs). It discusses SSD development and history, structure, memory, controllers, performance advantages over HDDs, applications, and key enterprise leaders. The presentation was given on April 18, 2014 about SSDs as a replacement for traditional hard disk drives.
3. Introduction
A solid-state drive(SSD)is a data
storage device that uses solid state
memory to store persistent data. It
is flash based storage device and It
uses same I/O interface developed
for hard disk drives.
SSDs do not have any moving
mechanical components, which
distinguishes them from traditional
magnetic disks such as hard disk
drives(HDDs).
In contrast, SSDs
use microchips that retain data in
non-volatile memory chips and
contain no moving parts.
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4. Development & History
The origins of SSDs came from the 1950s using
two similar technologies, magnetic core
memory and card capacitor read-only
store(CCROS) These auxiliary memory units as
they were called at the time, emerged during the
era of vacuum tube computers.
Later, in the 1970s and 1980s, SSDs were
implemented in semiconductor memory for
early supercomputer of IBM, Amdahl and Cry.
In 1995, M-Systems introduced flash-based solid-
state drives. They had the advantage of not
requiring batteries to maintain the data in the
memory (required by the prior volatile memory
systems), but were not as fast as the DRAM-
based.
Flash-based SSDs
Origin
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6. Memory
Flash memory-based SSDs:
Use non volatile NAND flash memory.
Ability to retain the data without a constant
power supply.
Lower cost compared to DRAM.
Flash memory SSDs are slower than DRAM
solution.
DRAM-based SSDs:
Based on volatile memory such as DRAM.
Internal battery or an external AC/DC adapter is
needed to hold the data.
Ultrafast data access.
Primarily to accelerate application.
Higher cost compared to NAND flash memory.
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7. Controller
The controller is an embedded processor and executes
firmware level code.
Every SSD includes a controller i.e. an embedded processor
that executes firmware-level code and is one of the most
important factors of SSD performance.
Functions:
Error Correction(ECC).
Wear levelling.
Bad block mapping.
Read scrubbing and read disturb management.
Read and write caching.
Garbage collection.
Encryption.
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8. Bandwidth and interleave
• Without interleaving
– For read: 25+100 us per page
• 8000 reads/s = 32MB/s
– For write: 200+100 us per page
• 3330 writes/s = 13 MB/s
• With interleaving
– For read
• 10000 reads/s = 40MB/s
– For write
• 5000 writes/s = 20 MB/s
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9. Performance
• Read
– 25μs from page to data register
– 100μs transfer in the serial line
• Write
– Page granularity
– Sequentially with in a block
– Block must be erased before writing
– 200μs from register into flash cells
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10. Technical Comparison of SSD & HDD
Solid-State Drive Hard Disk Drive
Random access time 0.1 ms. Random access time 5-10 ms.
Read latency time very low. Read latency time high.
100MB/s to 500MB/s. 50MB/s to 100MB/s.
High Reliability. Low reliability.
SSDs have no moving parts to fail
mechanically.
HDDs have moving parts and are subject
to sudden failure.
Small and light weight. Relatively large and heavy.
Till now SSDs are available in size up to
512GB.
Till now HDDs are available up to 4TB .
Power Consumption 2watts 12 watts.18-Apr-14
11. Advantages
High performance-Significantly faster than a
standard HDD.
Faster seek time-Up to 60x faster than HDD.
Higher reliability-No moving parts.
Lower power-Lesser power consumption, cooler
operation.
Silent Operation-Ideal for post production
environments.
Light weight-Perfect for portable devices.
Wider Operating Temp.
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12. Disadvantages
They are more expansive than traditional hard
drives.
They currently offer less storage space then
traditional hard drives.
Slower write speed.
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14. 18-Apr-14
Privately Held, 2006, Gyeonggi-Do, S. Korea
Claims fastest enterprise class SSD
Very close ties to Seoul National University and Samsung
Distribution deal with Imation who is better known for optical
Controller IP from Indilinx, founded by other SNU graduates
NASDAQ: SMOD, 1985, Fremont, CA
61% of 2007’s $828.4 million revenue was generated by HP & Cisco
SMART recently purchased Adtron
Close ties to Francisco Partners, Silverlake, & Samsung
NASDAQ: STEC, 1985, Santa Ana, CA
Zeus IOPS is the highest performing enterprise class SSD
STEC’s differentiator is its in-house controller technology
Margins could be pressured as competitors improve product
performance
Mtron
SMART Modular
STEC
SSD-Enterprise Leaders
15. Conclusion
Faster Data Access
Less Power Usage
Higher Reliability
Latest high-end Laptops and Ultrabooks now
comes with SSD
In coming years SSD will replace HDD
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