SIMD is a class of parallel computers in Flynn's taxonomy. such machines exploit  data level parallelism, but not concurrency. SIMD is particularly applicable to common tasks like adjusting the contrast in a digital image or adjusting the volume of digital audio. Most modern CPU designs include SIMD instructions in order to improve the performance of multimedia use.

1. BY-Anissa Yagiek

2. CONTENT
 Introduction
 SIMD computer organization
 Space of SIMD computers
 Array & associative processors
 SIMD computer perspective
 Applications

3. Introduction
 SIMD is a class of parallel computers in Flynn's taxonomy.
 such machines exploit data level parallelism, but not
concurrency.
 SIMD is particularly applicable to common tasks like
adjusting the contrast in a digital image or adjusting the
volume of digital audio.
 Most modern CPU designs include SIMD instructions in
order to improve the performance of multimedia use.

5. SIMD computer organization
 In SIMD instructions there are multiple processing
elements supervised by the same control unit.
 All PEs receive the same instruction broadcast from the
control unit but operate on different data sets from distinct
data streams.
 The shared memory subsystems may contain multiple
modules.

6. Space of SIMD computers
 We use the term array processor exclusively for SIMD
computers using conventional random-access memory and
the term associative processor for SIMD computers using
associative memory.
 we divide the spaces of SIMD computers into five
subspaces based on word-slice and bit-slice processing and
number of control unit used

7.  Word-slice array processors
 Bit-slice array processors
 Word-slice associative processors
 Bit-slice associative processors
 Multiple-SIMD computers

8. Multiple-SIMD
 Multiple-SIMD computers form a special subclass of
MIMD computers
 Multiple instruction streams exits in multiple-array
processor
 Each instruction stream handles multiple data sets,as
SIMD array

9. Array and associative processors
 In 1958 Unger conceived a computer structure for spatial
problems
 A two-dimensional array of PEs is controlled by a common
master
 Unger’s machine was proposed for pattern –recognition
applications

11. VAMP
 In 1965 a vector arithmetic multiprocessor(VAMP) was
designed.
 It consists of a linear array of PEs with shared memory
modules and a shared arithmetic pipeline
 each PE is a virtual processor, having only a few working
registers in it
 This pipeline-array processor was designed to save
hardware in vector processing.

13. SIMD computer perspectives
 SIMD computers are special-purpose systems.
 For a specific problem environment they may perform
impressively.
 however array processors have some programming and
vectorization problems which are difficult solve.
 The reality is that array processor are not popular among
commercial computer manufacturers

14.  The performance is indicated under ideal programming
and resource allocation conditions.
 As the size of PE-array increases the performance should
increase linearly.
 The peak speed is also a function of the word length
especially for bit-slice operations.
 For vector processing the performance depends also on the
vector length.

15. Application areas that have been
suggested for array processors
 Matrix algebra
 Linear and integer programming
 General circulation weather modeling
 Image processing and pattern recognition
 Wind-tuned experiments
 Automated map generation
 Real-time scene analysis