# High Performance Parallel Computing

From dankwiki

CSE 6230 -- High Performance Parallel Computing

*weak scaling*- maximizing work performed per unit time*strong scaling*- minimizing time-to-solution

## Measures of parallel algorithms

- Cost: proccount * exectime
- Overhead: Cost(P) - Cost(1)
- Speedup: exectime(1) / exectime(p)
- Efficiency: Speedup / p
- Scalable if
- Efficiency is O(1) as p approaches infinity (*not* 0)
- Work(p) is linear in p
- Fixed work per processor is O(1) as p approaches infinity (*not* 0)

- Isoefficiency: How fast must our working set grow to maintain constant efficiency as processors are added?

## Papers

- Amdahl's Law in the Multicore Era by MD Hill
- Lock-free algorithms page