WaFFLe

Managing thermal imbalance in contemporary chip multi-processors (CMPs) is crucial in assuring functional correctness of modern mobile as well as server systems. Localized regions with high activity, e.g., register files, ALUs, FPUs, and so on, experience higher temperatures than the average across the chip and are commonly referred to as hotspots. Hotspots affect functional correctness of the underlying circuitry and a noticeable increase in leakage power, which in turn generates heat in a self-reinforced cycle. Techniques that reduce the severity of or completely eliminate hotspots can maintain functional correctness along with improving performance of CMPs. Conventional dynamic thermal management targets the cores to reduce hotspots but often ignores caches, which are known for their high leakage power consumption. This article presents WaFFLe , an approach that targets the leakage power of the last-level cache (LLC) and hotspots occurring at the cores. WaFFLe turns off LLC-ways to reduce leakage power and to generate on-chip thermal buffers. In addition, fine-grained DVFS is applied during long LLC miss induced stalls to reduce core temperature. Our results show that WaFFLe reduces peak and average temperature of a 16-core based homogeneous tiled CMP with up to 8.4 ֯ C and 6.2 ֯ C, respectively, with an average performance degradation of only 2.5 %. We also show that WaFFLe outperforms a state-of-the-art cache-based technique and a greedy DVFS policy.

Enhanced Data Privacy Using Vertical Fragmentation and Data Anonymization Techniques

The use of online net banking official sites has been rapidly increased now a days. In online transaction attackers need only little information to steal the private information of bank users and can do any kind of fraudulent activities. One of the major drawbacks of commercial losses in online banking is fraud detected by credit card fraud detection system, which has a significant impact on clients. Fraudulent transactions will be discovered after the transaction is completed in the existing novel privacy models. As a result, in this paper, three level server systems are implemented to partition the intermediate gateway with better security. User details, transaction details and account details are considered as sensitive attributes and stored in separate database. And also data suppression scheme to replace the string and numerical characters into special symbols to overcome the traditional cryptography schemes is implemented. The Quasi-Identifiers are hidden by using Anonymization algorithm so that the transactions can be done efficiently.

Stability of Parallel Server Systems

A parallel server system is a queueing system in which jobs are routed upon their arrivals to one of several buffers, each handled by a different server. The main operational and theoretical problem in such systems is to find an efficient routing policy that maximizes their throughput (or minimizes waiting times). The paper “Stability of Parallel Server Systems” considers a large class of routing policies, which includes the most prevalent policies studies in the literature, under the assumption that routing errors may occur because ofincomplete information about the state of the system at decision epochs. The stability region for this class of policies is studied as a function of the error probability, and it is shown that the standard stability condition, namely, that the traffic intensity is smaller than one, does not guarantee that the system is stable.