The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Heterogeneous memory management combined with server virtualization in datacenters is expected to increase the software and OS management complexity. State-of-the-art solutions rely exclusively on the hypervisor (VMM) for expensive page hotness tracking and migrations, limiting the benefits from heterogeneity. To address this, we design HeteroOS, a novel application-transparent OS-level solution for...
The Moodle portal of our faculty is running in a virtualized environment together with other about 50 application servers and 60 virtualized desktops. Increasing traffic on the site (reaching over 400 000 views/posts monthly) forced us to assess its performance impact on the virtualization environment. The performance analysis identified processor cycles and disk operations as the bottlenecks of the...
FPGAs are being incorporated into contemporary datacenters in order to improve computational capacity, power consumption, and processing latency. Efficiently integrating FP-GAs in datacenters is, however, quite challenging. Ideally, smaller tasks could share a device and the cloud management layer would be able to partially reconfigure the device to allocate its free resources to incoming tasks. Moreover,...
Attacks on memory, revealing secrets, for example, via DMA or cold boot, are a long known problem. In this paper, we present TransCrypt, a concept for transparent and guest-agnostic, dynamic kernel and user main memory encryption using a custom minimal hypervisor. The concept utilizes the address translation features provided by hardware-based virtualization support of modern CPUs to restrict the...
Virtualization techniques have shown to report benefits to data centers and other computing facilities. In this regard, not only virtual machines allow reducing the size of the computing infrastructure while increasing overall resource utilization but also virtualizing individual components of computers may provide significant benefits. This is the case, for example, for the remote GPU virtualization...
The use of Graphics Processing Units (GPUs) has become a very popular way to accelerate the execution of many applications. However, GPUs are not exempt from side effects. For instance, GPUs are expensive devices which additionally consume a non-negligible amount of energy even when they are not performing any computation. Furthermore, most applications present low GPU utilization. To address these...
After a sequence of creation and destruction of virtual machines (VMs) in an on-premises Cloud computing platform, the scheduling decisions to host the VMs are far from being optimal and the fragmentation of the physical resources may impede the platform to host some VMs despite the free available virtualization resources. This paper describes a Virtual Machine Consolidation Agent that addresses this...
The rapid revolution of cloud computing model is accompanied by huge amounts of energy consumed by the cloud data centers. So, enhancing the energy efficiency of those data centers has become a major challenge. This paper tackles the problem of enhancing the energy consumption of cloud data centers by proposing a novel virtual machine placement strategy. The proposed strategy suits both static and...
Cloud computing is an on-demand access model for computing resources most notably embodied by the OpenStack project. As of release Liberty, OpenStack supports provisioning Bare-metal, Virtual machine (VM) and container based hosts. These different hosts incur different overheads. Consequently, the main goal of this paper is to empirically quantify that overhead through a series of experiments. The...
The resource allocation is an important concept in cloud computing. It is an emerging technology in modern computing systems, it provides an on demand services because it offers dynamic allocation of resources to provide reliable and high available services to the users. To manage the actual hardware resource of the underlying Physical Machine (PM), many number of jobs (user requests) are executed...
Studies have shown memory and computational needs vary independently across applications. Recent work has explored using hybrid memory technology (SRAM+NVM) in on-chip memories of multicore processors (CMPs) to support the varied needs of diverse workloads. Such works suggest architectural modifications that require supplemental management in the memory hierarchy. Instead, we propose to deploy hybrid...
With increasing deployment of virtual machines for cloud services and server applications, memory address translation overheads in virtualized environments have received great attention. In the radix-4 type of page tables used in x86 architectures, a TLB-miss necessitates up to 24 memory references for one guest to host translation. While dedicated page walk caches and such recent enhancements eliminate...
Non-volatile memory (NVM) provides persistence with dynamic random access memory (DRAM)-like performance. This paper presents SwapX, an NVM-based hierarchical swapping framework for guest operating systems (OSs) in virtual machines (VMs). SwapX works in a cluster connected to a NVM pool, where each server is equipped with both NVM and DRAM to provide hierarchical swapping service for VMs. SwapX: 1)...
Instead of scaling an application and data around the computer, programmers can use a software-defined server—an inverse hypervisor—in which multiple physical machines run a single virtual machine. Memory can be expanded as needed without modifying the application or limiting its data.
Novel non-volatile memory is considered as a future replacement for conventional main memory. While besides persistence non-volatile memory technologies promise higher storage density and lower power demand, they also possess an asymmetry between fast read and slow write access times. The latter can be in the order of 2x to even 20x. While persistent main memory per se asks for novel system software...
As the users on the cloud network increase, the consumption of the Compute, Network and Storage resources also increases. This leads to increase in the cost of deployment, configuration and maintenance. Hence, the Capital Expenditure (CAPEX) and Operational Expenditure (OPEX) of the organization providing the cloud network increases. Network Function Virtualization (NFV) is a technology which virtualizes...
Graphics processing Units (GPUs), which originally designed for computer graphics applications, have been widely adopted to general purpose computing in many domains owing to their massive computational power. In the era of cloud computing, GPU virtualization becomes an important technique for the better management of GPUs in data centers. However, most of current solutions are not full virtualization...
As the number of cloud users are increasing, it becomes essential for cloud service providers to allocate the right amount of resources to virtual machines, especially during live migration. In order to increase the resource utilization and reduce waste, the providers have started to think about the role of over-allocating the resources. However, the benefits of over-allocations are not without inherent...
PCM (Phase Change Memory) as next generation non-volatile storage media, has shown more better properties. However, there is no avoiding the fact that PCM has poor write performance and endurance, comparing with DRAM (Dynamic Random Access Memory). Another engine that drives this paper is the development of the cloud computing, which carries more and more virtual machine applications. Therefore, we...
IOPS performance as one of the important variables in the selection of storage would be devastasting if the server used for virtualization. If within one server has more than one virtual machine, the performance is given on those servers will be reduced and not optimal. Therefore, to increase the need for the use of server storage performance accelerator. Currently, PernixData FVP already implemented...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.