DE Mastery GitHub

Foundations of distributed data · FND-01

Why distributed?

  • 2 h

From your world. Why Redshift has a leader node and compute nodes; when one big box + DuckDB beats a cluster

Explain to a colleague who knows SQL but not distributed systems:

"Why does adding more machines eventually stop making my query faster, and how do I decide whether to use one big box or a cluster at all?"

Talk for about 5 minutes. Use a Redshift leader/compute analogy.

Rubric (self-check — aim for 5/6)

  • States the two limits that force distribution: capacity and time/deadline.
  • Explains Amdahl's law in words: the serial fraction caps the speedup at 1/(1-p).
  • Names a concrete serial bottleneck (final sort, collect() to driver, leader-node merge).
  • Contrasts scale up vs scale out and names the price of scale-out (the shuffle / network).
  • Gives a bytes-based reason why a single box with DuckDB can beat a cluster (columnar pruning → fewer bytes read).
  • States at least one concrete "do NOT distribute" condition (fits in RAM, serial-bound, or latency-sensitive small query).