computer architecture simd ola flygt växjö university [email protected] +46 470 70 86 49
TRANSCRIPT
Computer Computer ArchitectureArchitecture
SIMDSIMDOla Flygt
Växjö Universityhttp://w3.msi.vxu.se/users/ofl/
[email protected]+46 470 70 86 49
Outline
Design spaceGranularityConnectivityProcessor complexityLocal Anotomy
Fine grained architecturesCourse grained architectures
CH01
A typical SIMD system
The development of SIMD systems
Design space
There are several factors to consider when designing a SIMD. The most important ones are:GranularityConnectivityComplexity of processing elementLocal autonomy
Granularitymapping data to PEs
GranularityFine to coarse grain
Connectivity
Not all the types of connectivity for data parallel arch. are used in SIMD arch.
Performance of interconnection networks
There are several important parameters in an interconnection networkDiameter, the shortest path between the
two most distant nodesBandwidth, how many data exchanges
simultaneous in the networkBlocking, how many exchanges are
blocked
Performance of interconnection networks
N=128*128
1
1
256
28
14
14
1
N=128*128
1
16384
16384
28
14
16384
16384
Processor complexity
The design space for processor precisionSingle bit – fine grained, mainly for
image processingInteger – general computingFloating point – Coarse grain,
scientific computingFine grained -> more PEs
Local autonomy
Fine grained SIMDThe MPP system
Fine grained SIMDThe MPP processing
element
Fine grained SIMDThe MPP integrated circuit
Coarse grained SIMDThe CM5 processing
element
Coarse grained SIMDThe CM5 fat tree
connectivity
Coarse grained SIMDThe CM5 system
parameters