Mergesort notes

1
Mergesort notes

• Page 280, section 9.2.4 in Wilkinsons textbook
• Requires n/2 processors, not n processors
• Divide list in log2 1 steps, not log2 stop
  at two items per processor
• Merge sort integrates two sorted sublists, by
  taking the top item in either sorted list (as
  appropriate).
• Compare Degree of Parallelism. Calculate
  utilization/efficiency.
• Correct Wilkinsons processor allocation tree
• Compare a message-passing architecture to a
  shared-memory architecture better commo latency,
  fewer communications.
• Wilkinsons communication on pg 281 implies a
  mapping. Examine mapping to a overlapped group
  architecture.