Performance Benchmarking & Tuning Flashcards
7 cards from real CSI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Performance Benchmarking & Tuning flashcards as text
Which tool is commonly used to benchmark web server throughput by simulating thousands of concurrent HTTP requests?
Answer: Apache JMeter or wrk
Apache JMeter and wrk are purpose-built load generation tools that simulate high numbers of concurrent HTTP clients to measure web server throughput and latency.
When performing a Java application performance tuning, reducing GC pause times is best achieved by:
Answer: Switching to a low-pause collector like G1GC or ZGC and right-sizing heap regions
Low-pause collectors like G1GC and ZGC are designed to perform incremental collection, limiting stop-the-world pauses while right-sizing heap regions reduces fragmentation.
A performance test environment should mirror production as closely as possible primarily to:
Answer: Ensure benchmark results are representative of real-world behavior
If the test environment differs significantly from production, benchmark results may not predict actual production performance, leading to invalid capacity planning.
What is 'connection pooling' and why does it improve database performance?
Answer: Reusing pre-established DB connections to avoid repeated handshake overhead
Connection pooling maintains a set of open database connections that are reused across requests, eliminating the latency of establishing a new connection for every query.
In a microservices architecture, which pattern helps prevent a slow downstream service from causing cascading failures that degrade overall system performance?
Answer: Circuit breaker pattern
The circuit breaker pattern detects repeated failures to a downstream service and short-circuits calls to it, preventing thread pool exhaustion and cascading degradation.
Which Linux command provides a real-time view of per-process CPU, memory, and I/O usage useful for on-host performance diagnostics?
Answer: htop or top
htop and top provide a live, refreshing view of per-process resource consumption, making them the standard tools for interactive on-host performance diagnostics.
What does 'throughput' measure in the context of system performance benchmarking?
Answer: The number of requests or transactions completed per unit of time
Throughput measures the rate at which a system successfully processes work, typically expressed as requests per second or transactions per second.