Intelligent RAM

A microprocessor into a memory chipA microprocessor into a memory chip

Introduction to IRAM1

2

IRAM-Architecture3

Advantages of IRAM4

Outline

Disadvantages of IRAM5

M6

Inspiration of IRAM

Applications of IRAM

IIntelligent ntelligent RRandom andom AAccess ccess MMemoryemory

Introduction to IRAM

• History In a 1996–2004 research project in the

Computer Science Division of the University of California, Berkeley, the Berkeley IRAM project explored Computer Architecture enabled by the wide bandwidth between memory and processor made possible when both are designed on the same IC.

• Intelligence stands for Microprocessor and RAM stands for memory

• Merges RAM and Processor

Fig. 1 IRAM

Inspiration of IRAM

• Why we need IRAM???

problems: Processor-Memory Performance Gap “AWKWARDNESS” of high capacity DRAM chips

Inspiration of IRAM

• Solution of problems Provide a more cache memory

Put the processor on SRAM Put the processor in DRAM

• Why select DRAM ??? DRAM is 20 times denser than SRAM. Thus, IRAM enables a much larger amount of on-chip memory

than is possible in a conventional architecture.

Inspiration of IRAM

Time to be double

demand for processing power and memory

2 months

Microprocessor 18 months

DRAM 120 months

IRAM Architecture

• The Key Technologies behind the IRAM technology are,1) Vector Processing2) Embedded DRAM and3) Serial I/O Vector Processing

1) Vector Processing: Vector architecture deals with vector processing so represents only PROCESSOR architecture

Helps to study parallel processing of IRAM Parallel processing carried out by virtual processing of

IRAM processor

IRAM Architecture

Vector Architecture of IRAM

• Advantages of Vector Processing:

high performance on demand for multimedia processing

low power for issue of control logic

Because of less Complexity in design it’s cheap and very easy in implementation

IRAM Architecture

2) Embedded DRAM :

• Embedded technology means a chip is embedded into a device for control and well execution of operations of that particular device.

• During the fabrication the memory chip is embedded into the microprocessor to produce IRAM. Thus IRAM becomes a single chip into which both memory and processor are integrated for high quality performance due to their coexistence.

• ADVANTAGES: High Bandwidth Low latency Memory Access frequency low Memory Flexibility

IRAM Architecture

3) Serial I/O Vector Processing:

• Due to POOR Processing of earlier technology, Serial I/O Vector processing is used.

• Much more efficient and cost effective • Enhances performance of IRAM by offering smooth and

faster path for data transfer without hindering memory and processor performances

• ADVANTAGES: Offers very high band width in terms of GB/sec

which is greater than both Pin count is less Power Consumption is less than Parallel I/O

Advantages of IRAM

Lower Latency

Energy Efficiency

Higher Bandwidth Decrease time delay due to not multiplexing addresses and less BUS length. Also doesn’t have parallel DRAMs and less no. of pins.

Energy per memory access = AEL1 + MRL1 x AEL2 + MRL2 x AEoff-chip

where AE = access energy and MR = miss rate

Doesn’t need of L2 cache. So energy Efficiency is HIGH.

RAM and Processor are on single chip so less BUS length and due to that Higher data transfer.

Advantages of IRAM

Board Area

 Memory Flexibility

Cost of Production

Fabrication of RAM and Processor is done in a single fabrication line.

Integrates several chips into ‘One Chip’. So, SMALL board area requires.

Over conventional designs is the ability to adjust both the size and width of the on-chip DRAM

Disadvantages of IRAM

Completely new Architecture

For the acceptance of this new technology we have to discard our current products and technologies

High Cost of Testing

Adding a processor would significantly increase the test time

Non Upgradeability of Memory

DRAM chips areembedded in theIRAM chip,So,we will not be able to upgradethe memoryfurther

Overheatingeven though theheat produced isLess compared toCurrent processorsit may overheat due to the smallarea

Applications of IRAM

• Scientific computing• Lossy Compression (JPEG, MPEG video and audio) • Cryptography (RSA, DES/IDEA, SHA/MD5) • Multimedia Processing (compress., graphics, audio

synth, image proc.) • Speech and handwriting recognition • Operating systems/Networking• Databases (hash/join, data mining, image/video

serving)• Language run-time support (stdlib, garbage

collection)

Applications of IRAM• Nowadays, GIGABYTE is

manufacturing IRAM commercially

Package Content 

• One GIGABTE i-RAM• One SATA 1.5Gb/s cable• One i-RAM CD Driver• One i-RAM Manual

References

• IRAM - Chips that remember and compute, IEEE International Solid State  Circuits Conference

• Vector IRAM - ISA and Micro-architecture, Computer Science Division, University of California, Berkeley

• Vector IRAM - A Media-oriented Vector Processor with Embedded DRAM, Computer Science Division, University of California, Berkeley

• A Media-enhanced vector architecture for embedded memory systems, Computer Science Division, University of California, Berkeley

• Memory-Intensive Benchmarks: IRAM vs. Cache-Based Machines, Computer Science Division, University of California, Berkeley

• IRAM - Overcoming the I/O Bus Bottleneck, Denver, CO, USA

• The energy efficiency of IRAM architectures, 24th Annual International Symposium on Computer Architecture

• http://iram.cs.berkeley.edu/• http://wikipedia.org

Any questions?