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@article{194648,
        author = {Khajamuddin Ansari and Nadim Ansari and Md Nafis Ansari and Bittu kr. Gupta and Javed Hussain},
        title = {Optimizing REST API Response Time in Spring Boot Applications Using Multi-Layer Caching Strategies: A Comparative Empirical Study},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {10},
        pages = {4765-4770},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=194648},
        abstract = {Modern web applications built on microservice architectures increasingly depend on REST APIs for inter-service communication and client-server data exchange. In high-concurrency environments, database access latency emerges as the primary bottleneck degrading response time and user experience. This paper presents a rigorous empirical evaluation of four caching strategies — No Cache (baseline), Spring Cache with ConcurrentHashMap, Redis distributed cache, and a novel Hybrid Two-Level Cache (L1 in-memory + L2 Redis) — integrated into a Spring Boot 3.2 REST API serving a real-world Study Group Finder application. Using Apache JMeter, we subjected each strategy to load tests with 10 to 500 concurrent users over 60-second windows, measuring mean response time, 95th percentile latency, throughput (requests/second), and cache hit ratio. Results demonstrate that the Hybrid Two-Level Cache reduces mean response time by up to 94.1% compared to the no-cache baseline (from 847ms to 49ms at 500 concurrent users) while achieving a 96.8% cache hit ratio and sustaining 312.4 req/s throughput. Redis alone provided 78.3% improvement, while ConcurrentHashMap improved latency by 85.2% but introduced consistency risks in distributed deployments. These findings provide actionable guidelines for selecting caching strategies in Spring Boot microservices based on deployment topology, consistency requirements, and load characteristics.},
        keywords = {Spring Boot, REST API optimization, caching strategies, Redis, ConcurrentHashMap, performance benchmarking, microservices, Apache JMeter, response time, throughput.},
        month = {March},
        }