bitonic sort in shared simd array processor
TRANSCRIPT
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Bitonic Sort in
Shared SIMD Array Processor
Anukul Chandra Panda, Pankaj K Sa{pandaa,pankajksa}@nitrkl.ac.in
Banshidhar [email protected]
Presented By :
Dilruk G.A. (148209B)
Jagoda S.D. (148214K)
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Index …
Background of Sorting
SIMD Array Processor
Bitonic Sort Algorithm
Conclusion
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Background of Sorting
Sorting of data is needed everywhere• Data Structures, Joins in databases, Searching Algorithms
Simple algorithms required O(n2)• Selection Sort, Insertion Sort, Bubble Sort
Even advanced algorithm take O(nLogn)• Merge Sort, Heap Sort, Cube Sort
Parallel sorting solve the problem• Bitonic Sort, Parallel Merge Sort
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SIMD Array Processor
Special purpose processor • Ex: multi core, GPU
Single Instruction , Multiple Data• One instruction work on multiple
data items simultaneously
Single Program Counter
Multiple Processing Elements (PEs)
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Bitonic Sorting Algorithm
List A: (3, 4, 7, 8) monotonically increasing.
List B: (6, 5, 2, 1) monotonically decreasing.
List AB: (3, 4, 7, 8, 6, 5, 2, 1) Bitonic list.
Bitonic list is two monotonic lists concatenated
together, one increasing and one decreasing.
For n elements n/2 comparators are using.
Repeatedly build Bitonic lists and then sort them.
Just logn stages are required to sort the Bitonic
list.
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Bitonic Sorting Algorithm
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Time Complexity
In line 2 a shared memory access is needed.
Line 26 need one more operation to write
data back to the array.
Within nested loop 2 memory references are
multiplied
Bitonic Sort
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8x monotonic lists: 16,11,14,10,17,15,12,134x bitonic lists: (16,11),(14,10),(17,15),(12,13)
Bitonic Sort
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8x monotonic lists: 16,11,14,10,17,15,12,134x bitonic lists: (16,11),(14,10),(17,15),(12,13)
Bitonic Sort
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4x monotonic lists: (11,16),(14,10),(15,17),(13,12)2x bitonic lists: (11,16,14,10),(15,17,13,12)
Bitonic Sort
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4x monotonic lists: (11,16),(14,10),(15,17),(13,12)2x bitonic lists: (11,16,14,10),(15,17,13,12)
Bitonic Sort
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4x monotonic lists: (11,16),(14,10),(15,17),(13,12)2x bitonic lists: (11,16,14,10),(15,17,13,12)
Bitonic Sort
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2x monotonic lists: (10,11,14,16),(17,15,13,12)1x bitonic lists: (10,11,14,16,17,15,13,12)
Bitonic Sort
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sorting
Bitonic Sort
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sorting
Bitonic Sort
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sorting
Bitonic Sort
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sorting
Bitonic Sort
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sorting
Bitonic Sort
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Done
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Bitonic Sorting Example …
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Bitonic Sorting Example …
Saturday, April 15, 2023 22
Bitonic Sorting Example
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