What is speculative execution in Hadoop?

Updated May 16, 2026

Short answer

It runs duplicate tasks to handle slow nodes.

Deep explanation

Hadoop launches backup tasks if a task is slow to ensure faster completion.

Real-world example

Preventing delays due to slow servers in clusters.

Common mistakes

  • Enabling it in already optimized clusters unnecessarily.

Follow-up questions

  • When should it be disabled?
  • Does it increase cost?

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