VM (virtual machine) scheduling is a fundamental topic of virtualization, and fairness is its important design goal. Most VMMs (virtual machine monitor) provide PS (proportional share) schedulers. A PS scheduler assig...
详细信息
grid is susceptible to a number of software and hardware failures, so a deep understanding of and modeling the grid resource failures are a challenge and have significant influence on grid researching. However, due to...
详细信息
When multiple instances of an application running on multiple virtual machines, an interesting problem is how to utilize the fault handling result from one application instance to heal the same fault occurred on other...
详细信息
One of the motivations for virtualization technology is the desire to develop new services to enhance system security without trusting both the applications and the operating systems. An intrusion detection system is ...
详细信息
One of the motivations for virtualization technology is the desire to develop new services to enhance system security without trusting both the applications and the operating systems. An intrusion detection system is an example of such service that can help to isolate users from malicious attacks. In this paper, we propose hybrid-based intrusion detection architecture in virtual computing environment to detect and isolate harmful behaviors by real-time monitoring and alarming. In contrast to monolithic intrusion detection system, we introduce autonomous agents, acting independently of each other, to monitor the system. The agents are deployed in virtual machines to analyze actions occurring on the network and inside the hosts to determine whether they are potential security violations or not. Our architecture is implemented based on Xen, and the detection management center is deployed in a secure virtual machine.
This paper investigates the problem of Partitioning Skew1 in MapReduce-based system. Our studies with Hadoop, a widely used MapReduce implementation, demonstrate that the presence of partitioning skew causes a huge am...
详细信息
Virtual machine technology can enhance server utilization and consolidation on an individual physical machine. In a growing number of contexts, many of which re-quire high-performance networking inside of the system. ...
详细信息
The skyline operator has received considerable attention from the database community, due to its importance in many applications including multi-criteria decision making, preference answering, and so forth. In many ap...
详细信息
ISBN:
(纸本)9781424472611;9780769540597
The skyline operator has received considerable attention from the database community, due to its importance in many applications including multi-criteria decision making, preference answering, and so forth. In many applications where uncertain data a re inherently exist, i.e., data collected from different sources in distributed locations are usually with imprecise measurements, and thus exhibit kind of uncertainty. Taking into account the network delay and economic cost associated with sharing and communicating large amounts of distributed data over an internet, an important problem in this scenario is to retrieve the global skyline tuples from all the distributed local sites with minimum communication cost. Based on the well known notation of the probabilistic skyline query over centralized uncertain data, in this paper, for the first time, we propose the notation of distributed skyline queries over uncertain data. Furthermore, two communication- and computation-efficient algorithms are proposed to retrieve the qualified skylines from distributed local sites. Extensive experiments have been conducted to verify the efficiency and the effectiveness of our algorithms with both the synthetic and real data sets.
With the rapid development of virtualization technology as well as the good performance of computer hardware, virtual machine is beginning to gradually increase the performance of display to meet the needs of desktop ...
详细信息
Different virtual educational experiments (VEEs) have different frameworks and implementations in different disciplines. How to integrate different VEEs into one unified supporting platform is a challenging problem. T...
详细信息
Different virtual educational experiments (VEEs) have different frameworks and implementations in different disciplines. How to integrate different VEEs into one unified supporting platform is a challenging problem. The key problem of this integration is how to build a unified mathematical model for VEEs of diversified disciplines. However, most existing multi-domain uniform modeling (MDUM) approaches such as Modelica are research-oriented and lack of real time interaction, which does not meet the requirement of virtual experiments that are user-oriented and highly interactive. To tackle above problem, a Modelica-based interactive scheduling mechanism (MISM) for VEE is proposed. In MISM, user-oriented interaction is based on a best step length algorithm and an interactive event step algorithm. The throughput is considered in the former and the real time interaction is resolved by the latter. Experimental results shows that the approaches presented can meet the requirements of VEEs efficiently.
CPU time accounting is a basis of performance measurement and process scheduling in operating system. Accounting operations are traditionally completed in timer interrupt handler since timer interrupt is periodically ...
详细信息
CPU time accounting is a basis of performance measurement and process scheduling in operating system. Accounting operations are traditionally completed in timer interrupt handler since timer interrupt is periodically delivered to OS. However, when virtualization introduced, the CPU time is shared by multiple virtual CPUs (i.e., VCPU for short) and the virtual timer interrupt is paused for those ones be scheduled out. This makes the time accounting be inaccurate, and we should consider new method for VM to provide a stable and reliable data source, especially for the hardware-assisted virtual machines (i.e., HVM for short) which are not aware of VMM. The key point of accurate CPU time accounting is to distinguish the time allocated to “this VCPU” and “other VCPUs”. Para-virtualization (i.e., PV for short) achieves this goal by modifying the timer handling routines. For HVM, we propose an accurate accounting method (named XenHVMAcct) within Xen virtual platform. XenHVMAcct is designed by using the mechanisms of virtual interrupt and loadable kernel module, without direct modifications to guest OS. Experimental results show that our accounting method is as accurate as the PV solution.
暂无评论