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Performance Engineering & Optimization Topics

Backend system optimization, performance tuning, memory management, and engineering proficiency. Covers system-level performance, remote support tools, and infrastructure optimization.

Scalability & Capacity Planning

Analyzing how a system's performance changes as load grows and planning the resources to keep it healthy. Covers horizontal vs vertical scaling, throughput vs latency under load, headroom and saturation, load modeling, and forecasting capacity for expected traffic. Includes identifying the scaling bottleneck that will bind first as demand increases.

1 questions

Memory Management & Garbage Collection

Managing memory as a performance resource, in both managed-runtime and manual-allocation contexts. Covers allocation patterns, garbage-collection behavior and tuning, pauses and fragmentation, and detecting and fixing memory and resource leaks. Emphasizes the effect of memory pressure on throughput, latency, and stability.

7 questions

Performance Profiling & Bottleneck Analysis

Techniques for measuring where time and resources go in a running system and isolating the dominant bottleneck. Covers CPU/memory/allocation profiling, flame graphs, sampling vs instrumentation, hotspot identification, and distinguishing symptom from root cause. Emphasizes forming a measurement-first hypothesis before optimizing rather than guessing.

57 questions

Performance Trade-offs & Optimization Strategy

Deciding what to optimize, how far, and at what cost to other qualities. Covers performance vs readability/reliability/cost trade-offs, prioritizing the optimization with the highest payoff, knowing when a system is fast enough, and sequencing optimization work. Emphasizes optimization as a strategic engineering judgment rather than a reflex.

40 questions

Caching Strategies & In-Memory Optimization

Designing cache layers to cut redundant work and speed up reads, and the correctness costs that come with them. Covers cache placement (client/CDN/application/in-memory store), eviction policies, TTLs, write-through vs write-back, warming, and invalidation. Emphasizes hit-rate reasoning and the staleness/consistency trade-offs caching introduces.

47 questions

Performance Troubleshooting & Incident Response

Diagnosing and resolving performance problems in production, often under time pressure. Covers latency and slowdown investigation, reproducing and narrowing performance regressions, operational readiness for performance incidents, and restoring healthy behavior while preserving reliability. Emphasizes systematic debugging of live systems over offline experimentation.

48 questions

Performance Cost Optimization & Resource Efficiency

Optimizing for the money and resources a given level of performance consumes, not just raw speed. Covers cost-per-request reasoning, right-sizing compute and memory, efficiency of resource utilization, and trading performance against spend. Emphasizes treating cost and resource efficiency as first-class performance objectives.

44 questions

Concurrency & Asynchronous Performance

Using parallelism, concurrency, and asynchronous execution to improve throughput and responsiveness. Covers thread pools, event loops, async/non-blocking I/O, contention and lock overhead, and the coordination costs that limit parallel speedup. Focuses on the performance implications of concurrency choices rather than concurrency correctness alone.

41 questions

System Resource & I/O Optimization

Tuning how a system uses CPU, memory, disk, and network at the OS and I/O layer. Covers I/O throughput and blocking, buffering and batching, filesystem and kernel-level performance settings, and resource contention between processes. Includes OS-level performance tuning and diagnosing resource saturation on the host.

89 questions
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