Centralized Barrier Performance

• Latency

  • Centralized has critical path length at least proportional to p

• Traffic

  • About 3p bus transactions

• Storage Cost

  • Very low: centralized counter and flag

• Fairness

  • Same processor should not always be last to exit barrier
  • No such bias in centralized

• Key problems for centralized barrier are latency and traffic

  • Especially with distributed memory, traffic goes to same node

Previous slide

Next slide

Back to first slide

View graphic version