Introduction to Multi-core Architectures

1. Introduction to Multicore Architectures
V.M.Prabhakaran,
AP/CSE,
KIT-Coimbatore

2. Evolution of Core:
• Intel 8086
• Intel 286
• AMD Am286
• Intel 386
• Intel i486
• AMD Am386
• Cyrix cx486
• Intel Pentium
• AMD Am486
• Intel Pentium Pro
• AMD K6
• Intel Pentium II and Pentium II Xeon
• Intel Celeron
• AMD k6-3
• Intel Pentium III and Pentium III Xeon
• AMD Athlon
• Intel Pentium 4
• Intel Core 2
• Intel Pentium Dual Core
• Intel Core i5
• Intel Core i7

3. Core
Working

4. Single Core to Multicore Architectures

5. Type of CPU Description Capabilities
Single Core CPU
Has one core to process
different operations;
microprocessors were single
cores from the early 1970s on
Word processing, checking
email, surfing the Internet,
watching videos
Dual Core CPU
Has two cores to process
operations, able to process more
information at the same time
Flash-enabled web browsing,
video and conference chatting
Quad Core CPU
Contains two dual core
processors in one integrated
circuit
Voice-GPS systems, multi-
player gaming, video editing

7. Flynn's taxonomy
•Computers have single (S) or multiple (M) streams of
instructions (I) and data (D)
•Leading to four types of computers:
• SISD
• SIMD
• MISD
• MIMD.

8. SISD (Single Instruction, Single Data)
• Single Instruction, Single Data
(SISD) refers to an Instruction
Set Architecture
• Single processor (one CPU)
executes exactly one instruction
stream at a time
• Also fetches or stores one item
of data at a time to operate on
data stored in a single memory
unit.

9. SIMD (Single Instruction, Multiple
Data)
• SIMD architecture performs a
single, identical action
simultaneously on multiple data
pieces.
• Single control unit (CU) and
more than one processing unit
(PU).
• For e.g. a single instruction to
fetch multiple files.

10. MISD (Multiple Instruction Single Data)
• Have multiple processors.
• Each processor uses a different algorithm but uses the
same shared input data.
• MISD computers can analyze the same set of data using
several different operations at the same time.
• The number of operations depends upon the number of
processors.
• For e.g. fault-tolerant computers executing the same
instructions redundantly in order to detect and mask
errors.

11. MIMD(Multiple Instruction Multiple Data)
• Most modern desktop/laptops are
MIMD.
• Each processor in a multiprocessor
system can execute asynchronously
different set of the instructions
independently on the different set
of data units.
• Application : computer-aided
design/computer-aided
manufacturing, simulation,
modeling, communication switches
etc.