Performance Optimization¶
Balance workloads¶
assignment of work¶
- static assignment
- dynamic assignment
work granularity¶
- small work granularity
- large work granularity
Smarter task scheduling¶
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Distributed work queues
Scheduling fork-join parallelism¶
common programming patterns¶
Cilk Plus¶
cilk_spawn创建新的 independent work，并将其放入 thread0 的 queue 中，而非创建新的 thread；其他 thread 可以从 queue0 中 steal work
于是问题来了，thread0 是先运行 spawned child 还是 spawn 后面的 continuation 呢
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child first , stealing continuation
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continuation first, steal child
Techniques for reducing communication¶
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Improving temporal locality by changing grid traversal order
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Improving temporal locality by fusing loops
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Contention
Replicate contended resources (e.g., local copies, fine-grained locks) Stagger access to contended resources