Effective Cache Apportioning for Performance Isolation Under Compiler Guidance

With a growing number of cores in modern high-performance servers, effective sharing of the last level cache (LLC) is more critical than ever. The primary agenda of such systems is to maximize performance by efficiently supporting multi-tenancy of diverse workloads. However, this could be particularly challenging to achieve in practice, because modern workloads exhibit dynamic phase behaviour, which causes their cache requirements & sensitivities to vary at finer granularities during execution. Unfortunately, existing systems are oblivious to the application phase behavior, and are unable to detect and react quickly enough to these rapidly changing cache requirements, often incurring significant performance degradation. In this paper, we propose Com-CAS, a new apportioning system that provides dynamic cache allocations for co-executing applications. Com-CAS differs from the existing cache partitioning systems by adapting to the dynamic cache requirements of applications just-in-time, as opposed to reacting, without any hardware modifications. The front-end of Com-CAS consists of compiler-analysis equipped with machine learning mechanisms to predict cache requirements, while the back-end consists of proactive scheduler that dynamically apportions LLC amongst co-executing applications leveraging Intel Cache Allocation Technology (CAT). Com-CAS's partitioning scheme utilizes the compiler-generated information across finer granularities to predict the rapidly changing dynamic application behaviors, while simultaneously maintaining data locality. Our experiments show that Com-CAS improves average weighted throughput by 15% over unpartitioned cache system, and outperforms state-of-the-art partitioning system KPart by 20%, while maintaining the worst individual application completion time degradation to meet various Service-Level Agreement (SLA) requirements

Evaluation of patient presenting with acute respiratory distress at emergency department in a tertiary care hospital with special reference to bed side thoracic ultrasound

Introduction: Heterogeneous group of patients present with shortness of breath at emergency department. Initial and rapid diagnosis may be lifesaving. Bilateral diffuse anterior B-lines (3 or more) along with lung sliding (B-Profile) have been demonstrated to predict acute hemodynamic pulmonary edema (AHPE) in the BLUE (Bedside Lung Ultrasound in Emergency) protocol. Objectives: The objectives of this study are to find out causes of acute onset of dyspnea with special reference to bedside lung ultra sound. Methodology: In this study total number of the cases (N=438) were divided in acute hemodynamic pulmonary edema (AHPE Group, n=194) [i.e. B-Profile or (B/L) interstitial syndrome (3 & 3+ B-Line in all six BLUE points with lung sliding bilaterally)] and in the other – Group (n=244)[A/C/A-B profile]. Results: This AHPE-Group has significant low ejection fraction (44.28±10.92 with P value = 0.0001); significant low saturation at presentation (82.82±13.91 with P value = 0.0001) and significant high blood lactate level (2.41±1.91 with P value =0.0049).Total numbers of consolidation (pneumonia) found by bedside ultrasound in “Other” group was significantly higher than AHPE group (P value = 0.02426). Conclusion: Bedside lung ultrasound is a very useful tool to evaluate acute onset of dyspnea and to initiate prompt management