CloudScope: diagnosing and managing performance interference in multi-tenant clouds

© 2015 IEEE.Virtual machine consolidation is attractive in cloud computing platforms for several reasons including reduced infrastructure costs, lower energy consumption and ease of management. However, the interference between co-resident workloads caused by virtualization can violate the service level objectives (SLOs) that the cloud platform guarantees. Existing solutions to minimize interference between virtual machines (VMs) are mostly based on comprehensive micro-benchmarks or online training which makes them computationally intensive. In this paper, we present CloudScope, a system for diagnosing interference for multi-tenant cloud systems in a lightweight way. CloudScope employs a discrete-time Markov Chain model for the online prediction of performance interference of co-resident VMs. It uses the results to optimally (re)assign VMs to physical machines and to optimize the hypervisor configuration, e.g. the CPU share it can use, for different workloads. We have implemented CloudScope on top of the Xen hypervisor and conducted experiments using a set of CPU, disk, and network intensive workloads and a real system (MapReduce). Our results show that CloudScope interference prediction achieves an average error of 9%. The interference-aware scheduler improves VM performance by up to 10% compared to the default scheduler. In addition, the hypervisor reconfiguration can improve network throughput by up to 30%

Some Classes Of Semigroups That Have Medial Idempotent And Some Construction Theorem

It's known that the set of idempotents of the semigroup, plays an important role forthe structure of this semigroup. Specially, in the regular semigroups, an importantrole plays presence of the medial idempotent and normal medial idempotent.Blyth,T. S and R. B. McFadden have studied and constructed the regular semi groups which contain a normal medial idempotent in terms of idempotent-generated regular semi groups with a normal medial idempotent and inverse semigroups with anidentity. M.Loganathan has described the construction of the regular semigroupswhich contain a medial idempotent. In this paper we will study further properties of medial idempotents on abundant semigroups. We will apply also the constructiontheory of abundant semigroups with a medial idempotent to quasi-adequate semigroups and will make a description of structure of those subsemigroups

The Effects of a Three Months Exercise on Physical Fitness, Body Composition and Some Blood Parameters in Sedentary Middle Aged Female

In this study, we aimed to investigate the effects of three months of aerobic exercise on physical fitness, body composition and some blood parameters in sedentary Female. 45 sedentary Female with an average age of 36.11±1.04 years, high of 158.9 ±0.76 cm and weight of 70.83 ±1.67 kg have been selected. Sedentary Females were trained through an aerobic exercises programmed one hour a day for three days a week.  The aerobic exercise time was on 12 weeks. Setting-up exercises and training in each training session were arranged in such a way as to make each woman’s heart rate to between a levels of 130-140 beats per minute. Statistical analysis were done with Paired-t test, Variance analysis and Scheffe tests. At the end of the three months exercise programmed, a decrease of %9.06 in body weight, %9.96 in systolic blood pressure, %6.94 in diastolic blood pressure, %12.42 in total cholesterol, %22.44 in Triglyceride, %21.16 in low density lipoprotein and %21.4 in fat content ratio have been registered. However, there were increases of %26.22 in hand grip power, %63.83 in the maximum oxygen transfer, %6.2 in aerobic strength and %16.34 in high density lipoprotein. Even though the three months exercise has produced significant effect to on systolic blood pressure, jumping, high density lipoprotein cholesterol, Apo-B, Triglyceride, Hip circumference at .01 level. On number of heart beats, hand grip power, waist circumference, the maximum oxygen transfer, Low density lipoprotein cholesterol, Apo A I and fat contents, diastolic blood pressure and aerobic strength at .05 level. Conclusions: The result of three months low intensity aerobic exercises have shown the fact that such exercises could improve high density lipoprotein cholesterol values and physical fitness. Also by the changes of body fat, Triglyceride, total cholesterol and low density lipoprotein cholesterol values parameters it reduces body parameters. The risk for cardiovascular problems are reduced on sedentary females. Aerobic exercises programmers may be recommended to reduce hypertension, weight loss, diabetes, cardiovascular diseases or metabolic diseases on sedentary females between 130-140 heart rate

Kinetic Signatures and Intermittent Turbulence in the Solar Wind Plasma

A connection between kinetic processes and intermittent turbulence is observed in the solar wind plasma using measurements from the Wind spacecraft at 1 AU. In particular, kinetic effects such as temperature anisotropy and plasma heating are concentrated near coherent structures, such as current sheets, which are non-uniformly distributed in space. Furthermore, these coherent structures are preferentially found in plasma unstable to the mirror and firehose instabilities. The inhomogeneous heating in these regions, which is present in both the magnetic field parallel and perpendicular temperature components, results in protons at least 3-4 times hotter than under typical stable plasma conditions. These results offer a new understanding of kinetic processes in a turbulent regime, where linear Vlasov theory is not sufficient to explain the inhomogeneous plasma dynamics operating near non-Gaussian structures.Comment: 4 pages, 3 figures, submitted to Physical Review Letter

Paradigma tauhid dalam pelaksanaan tanggungjawab sosial korporat (CSR) / Norajila Che Man, Muhammad Rahimi Osman and Mohd Faizal P.Rameli

Tanggungjawab sosial korporat (CSR) memainkan peranan yang signifikan dalam perkembangan sektor perniagaan dan korporat di seluruh dunia. Perbahasan dan perbincangan mengenai konsep ini telah melalui satu proses yang panjang bermula seawal 1930-an sehingga sekarang melibatkan ruang lingkup yang berbagai seperti hubungan CSR dengan prestasi syarikat, bentuk pelaksanaan CSR yang berkesan, manfaat yang diperoleh dari program CSR dan sebagainya. Konsep tanggungjawab sosial korporat ini bukan merupakan perkara yang asing dalam ajaran Islam kerana pada asasnya elemen-elemen kebajikan dan keprihatinan kepada sesama manusia telah diterapkan dalam Islam. Elemen-elemen seperti keadilan sosial, persaudaraan, tanggungjawab individu, kedermawanan dan sebagainya telah berakar umbi dalam Islam sebagai mana dinyatakan dalam al-Quran dan al-Sunnah. Kertas kerja ini akan membincangkan mengenai konsep dan teori CSR menurut Barat dan elemen-elemen asas ICSR serta menilai peranan tauhid yang menjadi asas kewujudan konsep ICSR. Kertas kerja ini akan menggunakan kaedah analisis kandungan daripada sumber primer dan sekunder bagi mendapatkan maklumat berkaitan CSR dan ICSR. Dapatan awal kajian mendapati elemen tauhid merupakan asas utama pembentukan konsep ICSR kerana penyaksian dan kepercayaan kepada Allah SWT akan membentuk individu bertakwa yang memelihara hubungannya dengan Allah SWT, sesama manusia dan makhluk yang lain

An Electronically Reconfigurable Patch Antenna Design for Polarization Diversity with Fixed Resonant Frequency

In this paper, an electronically polarization reconfigurable circular patch antenna with fixed resonant frequency operating at Wireless Local Area Network (WLAN) frequency band (2.4-2.48 GHz) is presented. The structure of the proposed design consists of a circular patch as a radiating element fed by coaxial probe, cooperated with four equal-length slits etched on the edge along x-axis and y-axis. A total of four switches was used and embedded across the slits at specific locations, thus controlled the length of the slits. By activating and deactivating the switches (ON and OFF) across the slits, the current on the patch is changed, thus modifying the electric field and polarization of the antenna. Consequently, the polarization excited by the proposed antenna can be switched into three types, either linear polarization, left-hand circular polarization or right-hand circular polarization. This paper proposes a simple approach that able to switch the polarizations and excited at the same operating frequency. Simulated and measured results of ideal case (using copper strip switches) and real case (using PIN diode switches) are compared and presented to demonstrate the performance of the antenna

Semi-Supervised First-Person Activity Recognition in Body-Worn Video

Body-worn cameras are now commonly used for logging daily life, sports, and law enforcement activities, creating a large volume of archived footage. This paper studies the problem of classifying frames of footage according to the activity of the camera-wearer with an emphasis on application to real-world police body-worn video. Real-world datasets pose a different set of challenges from existing egocentric vision datasets: the amount of footage of different activities is unbalanced, the data contains personally identifiable information, and in practice it is difficult to provide substantial training footage for a supervised approach. We address these challenges by extracting features based exclusively on motion information then segmenting the video footage using a semi-supervised classification algorithm. On publicly available datasets, our method achieves results comparable to, if not better than, supervised and/or deep learning methods using a fraction of the training data. It also shows promising results on real-world police body-worn video