Experimental Verification of Hyper-V Performance Isolation Quality Level

Consolidating multiple virtual machines into a single server has been widely adopted in cloud computing to improve system utilization. However, the sharing of physical CPUs among virtual machines in consolidated systems poses a new challenge in providing an illusion of continuous CPU execution to the guest operating systems (OS). Due to the time-sharing of physical CPUs, the execution of a guest OS is periodically interrupted, while the guest OS may not be aware of the discontinuity of virtual time against the real time. The virtual time discontinuity problem causes the delayed processing of critical OS operations, such as interrupt handling and lock processing. Although there have been several prior studies to mitigate the problem, they address only a subset of symptoms, require the modification of guest OSes, or change the processor architecture. This paper proposes a novel way to comprehensively reduce the inefficiency of guest OS execution in consolidated systems. It migrates the short-lived critical OS tasks to dedicated micro-sliced cores, minimizing the delays caused by time sharing. The hypervisor identifies the critical OS tasks without any OS intervention, and schedules the critical code sections onto the dynamically partitioned cores at runtime. The dedicated micro-sliced cores employ a short sub-millisecond quantum to minimize the response latencies for consolidated virtual machines. By readily servicing the critical tasks, the proposed scheme can minimize the adverse artifact of virtual machine consolidation without any modification of guest OSes.

Chapter 152 Electronic structure calculations for molecules containing lanthanide atoms

The article examines the essence of information technology in the contemporary world and its impact on management operating systems. The authors define the concept of "information technology" and the basic principles of its functioning. In addition, the paper identifies the most common methods and approaches to modeling management operating systems. The authors analyzed the impact of information technologies on the development of Ukrainian enterprises. They also presented the latest information technologies in enterprise management and their essential contribution to the economy, exports, and employment. The study analyzed the dynamics of IT services development in Ukraine and their impact on its economy. It also presented a general analysis of operating systems in Ukraine and considered the possibilities of integrating information technology and innovative educational approaches. In addition, the paper examines the impact of information technology on the management of operating systems' security and presents the economic and technological effects that arise from implementing information technologies. This research aims to highlight the importance of information technologies in improving the efficiency and security of management operating systems.

Accompanying to the growing utilization and dependency on the internet and the ICT (Information and Communication Technology), the threat by hacking, malicious code and virus are rising as serious problems. Especially, the single server which is hosted by professional hosting companies is exposed to diverse attack, and then abused as malicious server. Even though responsibility for the security problem on the singe server is not to hosting company but to single server user, almost of users have little security awareness about the single server security. Thus, in this paper, we first survey the cause of increase of a single server, and then investigate reasons inducing vulnerable points of the single server. By inquiry with questionnaires about security awareness and necessity of security reinforcement for a single server, this paper suggests countermeasures for security of the single server including technical measures with low burden.

Cloud provider APIs have emerged as the de facto operating system for the warehouse scale computers that comprise the public cloud. Like single-server operating systems, they provide the resource allocation, protection, communication paths, naming, and scheduling for these large machines. Cloud provider APIs also provide all sorts of things that operating systems do not, things like big data analytics, machine learning model training, or factory automation. Somewhere, lurking within this menagerie of services, there is an operating system to a really big computer, the computer that today's application developers target. This computer works nothing like a single server, yet it also isn't a dispersed distributed system like the internet. It is something in-between. Now is the time to distill and refine a coherent system interface from the multitude of cloud provider APIs, preferably a portable one. In this paper we discuss what goes in, what stays out, and the principles that inform these decisions.

In this paper we describe a Parallel Performance Estimator suitable for the comparative evaluation of parallel algorithms. The Estimator is designed for SPMD programs written in either C or FORTRAN. Simulation is used to produce estimates of execution times for varying numbers of processors and to analyse the communication overheads. Results from the estimator are compared with actual results (obtained on a 16 processor IBM SP2 machine) for an Alternating Direction Implicit (ADI) solver of linear equations and for a Parallel Sort by Regular Sampling (PSRS) sorting program. In both cases the plots of Execution Time versus Number of Processors are accurate to 20% and show all of the features of the equivalent plots of the measured data.KeywordsExecution TimeParallel ProgramProcessor ArrayEvent QueueAlternate Direction ImplicitThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

The well known divide-and-conquer paradigm has proved to be useful for deriving efficient algorithms for many problems. Several researchers have pointed out its usefulness for parallel processing; however, the problem of analyzing such parallel algorithms in a realistic setting has been largely overlooked. In this paper a realistic model for divide-and-conquer based algorithms is postulated; the efficiency of some algorithms is then analyzed, taking into account all relevant parameters of the model (time, data movement and number of processors.)

In this paper we study parallel algorithms for the Mesh-of-Processors architecture to solve visibility and related separability problems for sets of simple polygons in the plane. In particular, we present the following algorithms: All proposed algorithms are asymptotically optimal (for the Mesh-of-Processors) with respect to time and number of processors.

# Users, not geeks, should design interface {#article-title-2} EDITOR—With reference to the article by Majeed et al,1 the consultation is central to medicine, and information technology must facilitate it. With...

Information Technology has evolved over a period of time from Electronic Data Processors (EDP) to Cloud based technologies. Software is a critical component in this industry. The core product component in software is the set of instructions in the form of source code. During inception of the industry, source code was accessible at no cost. In the next era of information technology (1970's & 1980's), programs which were earlier available free of cost were sold at a price through licensing. During mid and early 1980's open source and hardware integrated software emerged. Similar trend was visible in system software market, especially in the operating system software market. Over a period of time Microsoft operating system emerged as one of the dominant players in the market. However, in the recent past Microsoft has considerably lost its market share in operating system products from 94.38% in June 2007 to 84% in May 2014. This paper captures the trend in operating system software market and analyses customers' preference to switch over from the current operating system. The trend in the market was analyzed through secondary data on market share and the customer preference to switch over was captured through a survey of engineers at various multinational IT firms in Bangalore. The study identified that the current trend could be moving towards open source or hardware integrated operating system from proprietary operating software. The survey identified that higher percentage of users preferred to switch over from the current operating system on desktops, laptops and workstations to either open source or hardware integrated operating system except servers.

The Naval Oceanographic Office has constructed a high-resolution geophysical database (GDB) for the Western Barents Sea describing the properties of the seafloor and subsurface sediment layers important to acoustic modeling. The original implementation of this database used a public domain geographic information system (GIS) called GRASS (Geographic Resource Analysis Support System). Subsequent versions use a commercial GIS, ARC/INFO. While GRASS and subsequently ARC/INFO address the needs of the Naval Oceanographic Office as well as the R&D community currently using GDB, its large data files, GIS system size, and database access time, limit the use of this database on Navy operational systems, where access time and disk space are limited. Additionally, the data stored in GDB are not immediately compatible with the Navy's standard propagation loss models. This paper discusses efforts made toward porting the Western Barents Sea GDB onto an operational system which include regionalizing the data to accommodate severe disk space limitations, new storage and retrieval methods, and on-the-fly conversion of GDB data to data types compatible with Navy standard models. The result is a full implementation of the Barents Sea GDB on a PC-based model operating system, without sacrificing many appealing features of the GIS.

: The North American Aerospace Defense Command (NORAD) and United States Northern Command (USNORTHCOM) (N-NC) crew training has been hindered by an inability to conduct dynamic training and exercises on multiple Command and Control (C2) systems. There was no common simulation injector because of stove-piped acquisitions and legacy interfaces that were incompatible with the Live-Virtual-Constructive Toolkits. The N-NC Joint Training and Exercise Directorate could not afford traditional replication or emulation of all C2 systems and their data sources, nor the inevitable sustainment costs. This paper presents a cost-effective solution to provide dynamic scenario injection into multiple C2 systems: leveraging server and desktop virtualization technology described in previous I/ITSEC papers. The virtualization process transforms stand-alone systems into functionally equivalent virtual machines (VMs). Server virtualization technology lets multiple VMs run as guests on a single host, and a host can support VMs running different operating systems. This allows entire processing strings, distributed throughout North America, to be converted into VMs on a single server. Because the VMs inherit the fidelity of the actual processors, their outputs are as authentic as the operational systems. These VMs feed processed simulation event data into actual C2 systems or equivalent VMs. Future operational system upgrades can be virtualized and then replace existing VMs without changing this infrastructure. Desktop virtualization technology allows users to run multiple VMs in separate windows on a common display. NNC exploited desktop virtualization to simplify the trainee and model operator's workspaces. They can view and manage multiple VMs with one monitor, keyboard and mouse (controlling simulations, lower echelon processing and operator interaction, and viewing C2 workstation displays).

Cybersecurity vulnerabilities of cardiac implantable electronic devices: Communication strategies for clinicians—Proceedings of the Heart Rhythm Society's Leadership Summit

Fortran code for SU(3) lattice gauge theory with and without MPI checkerboard parallelization

Program for quantum wave-packet dynamics with time-dependent potentials