:C MPI

1
???????C ? MPI???????

• ???
• 2008/1/27-31

2
Parallel Odd-Even Transposition Sort

• Initially,  n numbers are distributed to n
  processes, respectively.
• For each process with odd rank P, send its number
  to the process with rank P-1.
• For each process with rank P-1, compare its
  number with the number sent by the process with
  rank P and send the larger one back to the
  process with rank P.
• For each process with even rank Q, send its
  number to the process with rank Q-1.
• For each process with rank Q-1, compare its
  number with the number sent by the process with
  rank Q and send the larger one back to the
  process with rank Q.
• Repeat 1-4 until the numbers are sorted.

3
Parallel Shear Sort

• Shear sort is a classical sorting algorithm
  working in rounds on 2-dimensional meshes of
  processors. The basic idea of shear sort is to
  arrange the data into rows and columns in a gird
  allowing us to sort those rows and columns
  concurrently.
• Let's assume for now that N is a perfect square.
  We organize the elements into an array of cells
  sqrt(N) by sqrt(N). On each sorting pass, we
  alternately sort rows and columns (pass 1 for
  rows, pass 2 for columns, pass 3 for rows, and so
  on). We sort odd numbered rows from left to right
  and sort even numbered rows from right to left.

4
????

• http//www.cs.rit.edu/atk/Java/Sorting/sorting.ht
  ml
• http//www.cs.mu.oz.au/498/notes/node31.html
• http//pioneer.netserv.chula.ac.th/mveera/Algorit
  hmVisualization/SeniorProject2000/
• http//www.nscollegeprep.cps.k12.il.us/depts/cs/dy
  anek/ap/programs/shearSort/index.html