What is data partitioning?

Definition

Data partitioning assigns different portions of data to different computational resources. In distributed AI, a tensor may be split by examples, features, model dimensions, experts, or sequence positions, depending on the algorithm and hardware topology.

A useful partition balances work while minimizing data exchange and duplication. Poor boundaries can create uneven load, excessive communication, difficult synchronization, or expensive reshaping. The best partition depends on tensor shape, operation order, memory capacity, and network links.

ELI5

Data partitioning divides a large collection of data into smaller pieces that different computers or storage systems can handle. Good partitions let work happen in parallel without excessive copying or communication.

For example, an AI training job can send different batches of examples to several accelerators at the same time. If one partition contains much more work than the others, some machines finish early and wait, so the split should balance workload and match the hardware links.

Why is data partitioning important for parallel computing?

It determines which processor owns each piece of work and how much data must be exchanged before the overall result can be completed.

What makes a data partition inefficient?

An inefficient partition creates imbalanced work, excessive communication, duplicated data, costly reshaping, or synchronization that leaves processors idle.

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Definition card for data partitioning: What is data partitioning?

Data partitioning divides a dataset or tensor into defined pieces so different processors, workers, or storage nodes can handle them independently or in parallel.