Java · Senior · Theory

Tell me how JIT compilation works in HotSpot and what optimizations it performs. How does that affect the way you write and measure performance-critical code?

~4 min by voice

How to approach it

This checks whether the candidate understands the real mechanics of HotSpot: the interpreter, profiling, tiered compilation, speculative optimizations and deoptimization. The second thing it looks at is whether they can draw practical conclusions from that: measure correctly with JMH, warm up a service, and explain performance drops.

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Answers0

Avg. score—

Strong—

Practiced0

Topics

jvm jit

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Answer by voice

The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~4 min