{'fraction_non_alphanumeric': 0.021701388888888888, 'fraction_numerical': 0.0, 'mean_word_length': 5.703488372093023, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
A QoS Control Approach in Differentiated Web Caching Service

As the heterogeneity ofWeb clients increasing, the differentiated service becomes an important issue especially for e-commerce Web site. Web caching as a key accelerator on the Internet plays an important role in alleviating the client-perceived delay. To meet the Service Level Agreement (SLA) for clients without excessively over-provisioning resources, this paper proposes and evaluates a novel framework for enforcing Proportional Hit Rate. The framework combines the implement of Isolated Cache Model and the usage of control-theoretical approach for storage control. With system identification, the linear model is identified as well as the controller. At every sampling time, by dynamically reallocating storage spaces for different Web classes, the controller operates to guarantee the relationship of QoS metric among classes constant. The experimental results demonstrate the proposed approach achieves differentiated caching service with the enforcement of Greedy Dual Size Frequency (GDSF), Latest Recently Used (LRU) and Latest Frequently Used (LFU) cache replacement policies.