Reviewed by Aditya Kumar · Last reviewed 2026-03-24
RAM: Volatile, byte-addressable storage; faster than SSD; CPU accesses via memory controller; data in cache lines. DRAM (capacitors) vs. SRAM (flip-flops). WHY FOR DE: Spark, Pandas rely on memory; exceeding it causes spill and GC pressure. SCALABILITY: Cluster memory limits...
RAM: Volatile, byte-addressable storage; faster than SSD; CPU accesses via memory controller; data in cache lines. DRAM (capacitors) vs. SRAM (flip-flops). WHY FOR DE: Spark, Pandas rely on memory; exceeding it causes spill and GC pressure. SCALABILITY: Cluster memory limits parallelism; monitor OOM and GC. COST: Memory-optimized instances cost more; tuning (executor memory, off-heap) reduces waste.
Red Flag: Purely theoretical. Pro-Move: 'We tune Spark executor memory to leave headroom for off-heap; monitor GC pause—reduced from 5s to 200ms.'
According to DataEngPrep.tech, this is one of the most frequently asked General/Other interview questions, reported at 1 company. DataEngPrep.tech maintains an editor-reviewed database of 1,863 data engineering interview questions across 7 categories.