Scholarly article on topic 'Empirical Analysis of Server Consolidation and Desktop Virtualization in Cloud Computing'

Empirical Analysis of Server Consolidation and Desktop Virtualization in Cloud Computing Academic research paper on "Computer and information sciences"

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Academic research paper on topic "Empirical Analysis of Server Consolidation and Desktop Virtualization in Cloud Computing"

Hindawi Publishing Corporation Mathematical Problems in Engineering Volume 2013, Article ID 947234,11 pages http://dx.doi.org/10.1155/2013/947234

Research Article

Empirical Analysis of Server Consolidation and Desktop Virtualization in Cloud Computing

Bao Rong Chang,1 Hsiu-Fen Tsai,2 and Chi-Ming Chen3

1 Department of Computer Science and Information Engineering, National University ofKaohsiung, 81148 Kaohsiung, Taiwan

2 Department of Marketing Management, Shu Te University, 82445 Kaohsiung, Taiwan

3 Department of Computer Science and Information Engineering, National University of Kaohsiung, 81148 Kaohsiung, Taiwan Correspondence should be addressed to Bao Rong Chang; brchang@nuk.edu.tw

Received 11 September 2013; Accepted 10 October 2013 Academic Editor: Teen-Hang Meen

Copyright © 2013 Bao Rong Chang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Physical server transited to virtual server infrastructure (VSI) and desktop device to virtual desktop infrastructure (VDI) have the crucial problems of server consolidation, virtualization performance, virtual machine density, total cost of ownership (TCO), and return on investments (ROI). Besides, how to appropriately choose hypervisor for the desired server/desktop virtualization is really challenging, because a trade-off between virtualization performance and cost is a hard decision to make in the cloud. This paper introduces five hypervisors to establish the virtual environment and then gives a careful assessment based on C/P ratio that is derived from composite index, consolidation ratio, virtual machine density, TCO, and ROI. As a result, even though ESX server obtains the highest ROI and lowest TCO in server virtualization and Hyper-V R2 gains the best performance of virtual machine management; both of them however cost too much. Instead the best choice is Proxmox Virtual Environment (Proxmox VE) because it not only saves the initial investment a lot to own a virtual server/desktop infrastructure, but also obtains the lowest C/P ratio.

1. Introduction

Well-known public large-size cloud and private enterprise-owned cloud are currently leading cloud computing and services, for example, Amazon AWS, Google App Engine, and Windows Azure in public cloud and Saleforce.com and EMC2 in private cloud. In contrast, small-to-medium sized enterprises (SMEs), educational institutes, and social groups are also very eager to pursue the services they want based on virtual server in cloud (VSiC) [1] architecture due to cost reduction, performance escalation, and security improvement. With this service, the operational costs for the information system can be drastically reduced and it can quickly increase the competitiveness of its information system, which is sustained by the following advantages: centralized monitoring, quick management, dynamic optimization, and efficient backup.

Technically, unexpected situations with service-type servers, such as websites, databases, AP servers, and file servers, bring much trouble for enterprises. Once a service

stops its function, it can cause faulty data, stalled production lines, and interrupted operation procedures, leading to multiple losses. However, a physical host has problems of promptness of service transfer to another host, restarting the service, and inability to update data in real time. The hardware, information, and data will be obstacles for enterprises to overcome.

To solve the issues mentioned above, virtual machine management system or hypervisor [2], such as VMware ESX/ESXi Server, Microsoft Hyper-V R2 [3], and Proxmox virtual environment (Proxmox VE) [4], is able to deliver the virtual machine services for virtual server/desktop infrastructure with high availability in computing, secured networking, and consolidated storage. With this approach, users make it possible to adopt low cost thin clients (a low-end PC or PDA) to link to the system for the services [5], reducing IT purchasing cost and saving computation power because thin client devices are easier to setup where the chances of malfunction, heat crash, and computer virus are considerably

low. In addition, easy to use through wireless mobile computing environment gains peoples' attraction a lot.

As the virtualization architecture expands continuously, network storage services have become part of the virtualization architecture. Openfiler [6] is a storage management system used for disk read/write accessing in a shared storage among several virtual machines or servers in enterprises. It is a free and conducive system that supports both network-attached storage (NAS) [7] and storage area network (SAN) [7] functions. As installed, it can be managed via web browsers in conjunction with iSCSI shared storage (IPSAN) [7] technique to provide file accessing on cloud computing servers. One can also use logical unit number (LUN) [8] through iSCSI to complete the placement of block accessing for virtual machines that are created by VMware or Hyper-V. This paper will evaluate the performance of accessing to block storage area network with Openfiler.

The goal in this paper also wants to clarify a credibility of cost and benefits on infrastructure virtualization. Speaking of virtualization cost and benefits, we will give the exploration of total cost of ownership (TCO) and return on investment (ROI) individually in the following statements. ROI [9] related to two factors, savings and investment, is equal to savings/investment, where investment represents the sum of incremental investment in transition from physical to virtual (new servers, shared storage, software licenses & support, services and training, etc.). In addition to investment, TCO [10] yet includes IT administration and downtime cost. Apparently, ROI and TCO can be properly undertaken well according to how big infrastructure has been virtualized. In terms of virtualization, how many infrastructures can be virtualized that intuitively depend on the ratio of the virtual machines per core (VMs/core), the so-called consolidation ratio [11]. The consolidation ratio is a measurement unit that virtualiza-tion vendors use with extreme prudence to provide a rough idea of the server consolidation level that can be achieved on their hypervisors. Virtual infrastructure as we know has been classified into server virtualization and desktop virtual-ization. We will explore the consolidation ratio and TCO/ROI for both server and desktop virtualizations in this study.

In addition, how to appropriately choose the virtual machine management (i.e., hypervisor) for the desired server/desktop virtualization is a really tough problem of a trade-off between performance and cost before making the decision to deploy virtual server in cloud (VSiC) as a new IT. Given five hypervisors used to establish VSiCs, this paper introduces a composite index to represent the evaluated functional performance as well as formulates a proper equation to stand for the estimated virtualization cost so that a C/P ration will conclude a careful assessment about a variety of VSiCs discussed in this paper.

2. Structure of Virtual Machine and Shared Storage

The purpose of this session is to setup five different virtual servers in cloud (VSiC) and provide an appropriate assessment for every virtual machine monitor (i.e., hypervisor).

Table 1: Hypervisor architecture.

VMM Hypervisor architecture

VMware ESXi 5.0 (Redhat Linux) Bare-metal/monolithic

MS Hyper-V R2 (Windows Server 2008) Bare-metal/microkernel Proxmox VE* (Debian) Hosted

KVM* (Ubuntu Enterprise Server) Hosted

Xen* (Cent OS) Bare-metal/microkernel

*Open source.

These assessments can provide an optimal solution for SMEs, schools, and social groups. This research will setup and implement five heterogeneous virtual machine management systems which are (a) vSphere ESX/ESXi, (b) Hyper-V R2, (c) Proxmox virtual environment, (d) Ubuntu KVM [12], and (e) CentOS Xen [13], where they are shown in Figures 1, 2, 3, 4, and 5, respectively. Moreover, five heterogeneous hypervisors all link to a shared storage Openfiler through LAN, which is a type of IPSAN storage as shown in Figure 6.

Noted that vSphere ESX/ESXi Server, Hyper-V Server 2008 R2, or CentOS-based Xen required at least a stand alone machine for installation, Ubuntu Enterprise Server has to at least include 2 physical machines (Cloud Controller and Node Controller) and Proxmox VE at least a master or optionally adding multiple nodes as well.

As shown in Table 1, hypervisor includes all kinds of virtual machine architectures and types, hence referred to as heterogeneous virtual server in cloud. Virtual machine architectures are divided into hosted architecture, such as (a) and (b), and bare-metal architecture, such as (c), (d), and (e); its types are classified into paravirtualization, such as (d) and (e), full-virtualization, such as (a), (b), and (c), and hardwareassisted virtualization for all of them. This is because the new x86 machines, regardless of 32-bit or 64-bit, now support Intel VT-x and AMD-V virtual instructions.

3. Formulation of Consolidation Ratio and TCO/ROI

The aim ofthis section is first to understand the consolidation ratio of VMware ESX server as well as TCO/ROI evaluated at VMware TCO/ROI calculator [14]. Consolidation ratio means the number of VMs running in a server concurrently depending on the number of workloads and the average number of VMs per core. The max consolidation ratio per VMware ESX server is by default calculated as 1.5 VMs per core multiplied by the total number of cores per server [15]. That is, it gives 12:1 in ESX's server favor. Based on Taneja Group observations early in 2009 [16] during testing as well as their familiarity with a broad range of virtual server infrastructures, they claimed there are many realistic workloads under which ESX4 gains a 2: 1VM density advantage comparing with Hyper-V R2 and XenServer 5.5. Thus, we extensively proposed to analyze VM density according to a VMware official document for EXS server [14] and a testing report from consulting services [16] such that the consolidation ratio for the other hypervisors can be obtained.

Client

Thin client

Tablet PC

Cluster controller (CC) + node controller (NC)

Virtual machine

Windows Linux

ESX/ESXi server

ESX/ESXi package

Redhat linux kernel

Cloud controller (CLC)

vSphere client control tool

Administrator

Windows 7

Figure 1: vSphere ESX/ESXi server.

On the other hand, the ROI required for the transition to virtual infrastructure evaluates the percent of total saving/total cost, where total saving consists of capital expenditure, operational expenditure, and downtime cost; total cost is composed of new servers, storage, network storages, software license & support, server, and training [14]. TCO is the costs associated with operation of datacenter which include capital expenditure (servers, storage, and switches), operational expenditure (power & cooling, infrastructure administration labors, and rack space), and business agility (planned downtime, unplanned downtime, and business downtime) [14]. Furthermore, the TCO/ROI for the other hypervisors has been estimated carefully according to VM density and the ratio of ESX normalized performance index to anyone.

4. Empirical Analysis Method

With respect to the performance evaluation for the virtual machine monitor, a variety of guest OS and two well-known

test tools are adopted in this study. PassMark PerformanceTest 7.0 (at http://www.passmark.com/down-load/pt_download.htm) is applied to the test of virtual machine performance for the Windows series guest OS like Windows XP, Windows 7, and Windows Server 2003, and UnixBench 5.1.3 (at http://byte-unixbench.google-code.com/files/UnixBench5.1.3.tgz) is employed for Linux series guest OS like Ubuntu. According to evaluated performance score for each virtual infrastructure server, we derived the respective scores into a composite index, each hypervisor on (1) and (2), and sequentially normalized to be a value ranging from 0 to 1 on (3), where we refer to this as a normalized composite index related to virtual machine performance. In (1), WS; is a test score for various guest Windows OSs (e.g., Win XP, Win Server 2003, and Win 7) running in a VM, and accordingly, WSmean represents a mean test score for various guest OSs; in (2), LSmean stands for a mean test score for a guest Linux OS (e.g., Ubuntu and CentOS); in (3), CIvm means a VM composite index for a specific hypervisor, and two coefficients and Я2 act as a

Cluster controller (CC) + node controller (NC)

Hyper-V server 2008 R2

Cloud controller (CLC)

Administrator

Hyper-V manager

Windows 7

Figure 2: Hyper-V Server 2008 R2 server.

weighted average; in (4), CIvmt represents a normalized VM composite index for a specific hypervisor. Consider

WS, N '

Ij=1 LS,

CIvm = A1 ' LSmean + A 2 ' WSn

s.t. A1 + A2 = 1,

CIvm = cI

In order to achieve virtual infrastructure together with a shared storage, we first have to establish a set of block storage area network system called Openfiler and then mount shared storage to each virtual server. After that, we go for the performance evaluation of accessing block storage by using Linux hdparm command [17] to test disk reading speed. Likewise, we do the same thing as the above mentioned procedure to develop a composite index on (5) and its normalized composite index on (6) associated with storage-accessing speed performance. Finally, we derive the composite index

for total on (7) and a normalized one on (8). In (5), CSmean is a mean test score for cache read speed performance on a guest Linux OS in a VM, DSmean a mean test score for disk read speed performance, and CIsa a storage-accessing speed composite index; in (6), CIs% stands for a normalized storage-accessing speed composite index for a certain hypervisor; in (7), CI represents a composite index for a certain hypervisor for overall, and in (8), CI represents a normalized composite index. In terms of average, three sets of coefficients indicated by vj/v2, щ1щ, and are designated to act as a weighted average for equation in (5), (7), and (8), respectively. Consider

CIsa = ]1 ' CS mean + ]2 ' DSn

s.t. ]1 + V2 = 1,

— CIsa CI = sat

sat = CIsa '

CI = • CIvm + ^2 • CIsa

s.t. ш1 + ш2 = 1,

CI = • CIvm + % • CIsa s. t. + % = 1

In this paper, we mainly conduct a credibility of cost and benefits before and after infrastructure virtualization. Speaking of cost and benefit, we will explore the consolidation ratio and TCO/ROI of both server consolidation and desktop virtualizations as mentioned above. VMware ESX server is first chosen to evaluate its consolidation ratio and estimate TCO/ROI at VMware calculator webpage. The consolidation ratio and TCO/ROI of both server and desktop virtualiza-tions for the other hypervisors will be proportional to both its VM density (major part) and the ratio of ESX normalized composite index to alternative one (minor part). We broke the costs about capital expenditure, operational expenditure, and business agility into 13 items. Technically the table as listed in Table 2 gives us an insight to realize which item highly concerned with the VM density and/or normalized performance index ratio, which are derived from TCO/ROI calculation. Moreover, a formula for calculating the expenditure of TCO/ROI has been derived on (9) where VMDESX represents VM density for ESX server and VMDhypervisor for the other hypervisors; CostESX stands for the expenditure for ESX server and Costhypervisor for the other hypervisors. There is no the initial cost of software package for Proxmox VE,

Ubuntu KVM, and CentOS Xen due to open source software. However, the initial cost of ESX server software package (approximate US$ 12,668) is greater than that of Hyper-V R2 (approximate US$ 6,000). Consider

„ . . hypervisor

COSVe™or =IM1- VMDrcv

+ß-(l-

• CostESX + initial cost

s.t. 0 < a < 1 0 < ß < 1 a + ß = 1.

5. Experimental Results and Discussion

There are three experiments and the discussion presented in the following subsections.

Node controller (NC)

Virtual 0

Linux KVM

Cloud controller (CLC) + cluster controller (CC)

Administrator

Cluster controller (CC) Storage controller (SC)

Cloud controller (CLC) Walrus

Ubuntu enterprise server Cloud/cluster controller

Figure 4: Ubuntu KVM server.

5.1. Assessment of Virtual Machine Performance. The server hardware specification is listed in Table 3.

The resulting score is an average of various scores from test items, for example, CPU, memory, storage, network, and 2D graph. In the experiment, two testing softwares (PassMark PerformanceTest 7.0 and UnixBench 5.1.3) are applied to evaluate the virtual machine performance for hypervisors such as ESXi 5.0, Hyper-V R2, Proxmox VE, Ubuntu Enterprise Server KVM, and CentOS Xen. A summary of the virtual machine performances is shown in Table 4 as well as Figures 7 and 8.

Different guest OS is installed separately on each virtual machine and adds up to 5 VMs in each predetermined virtual machine monitor (one of the above-mentioned hypervisors). They are divided into Windows series and Linux series guest OSs. After that, the testing software will be taken to analyze a set of target items as mentioned above.

5.2. Performance Evaluation of VM Accessing Shared Storage. In the experiment, according to the same server hardware specification as mentioned above, Openfiler storage device is separately mounted onto five virtual servers in cloud to test disk-accessing speed. Tests carried out two disk-accessing

speed indicators, (a) timing cached reads (MB/sec) and (b) timing buffered disk reads (MB/sec) [18]. A summary of storage-accessing speed performances is shown in Table 5 as well as Figures 7 and 8.

5.3. Estimation of Consolidation Ratio and TCO/ROI. This part goes to the estimation of the consolidation ratio and TCO/ROI for each virtual server infrastructure as mentioned above. We choose VMware ESXi server as a benchmark and use VMware TCO/ROI calculator to yield its server/desktop consolidation ratio and TCO/ROI quantity. VMware ESX exceeds 2 times the workload capacity per server for the competitive hypervisors such as hypervisor-V R2, XenServer 5.5, and the others [16]. Accordingly, we assumed ESXi achieved 2: 1 VM density per server advantage over the other hypervisors in this study. Thus, ESXi achieved the consolidation ratio 12 : 1 in server virtualization as well as 96 : 1 in desktop virtualization because of 1.5 VM per core; instead the other hypervisors result in 6 : 1 in server virtualization as well as 48 : 1 in desktop virtualization. We estimate that TCO/ROI for alternative hypervisor is greatly proportional to its VM density (i.e., major part of estimation) and additionally adds somewhat fluctuations or changes to the evaluation of TCO

Figure 5: CentOS Xen server.

Cloud controller (CLC) + cluster controller (CC)

Windows server 2008 Hyper-V R2

Node controller (NC)

Virtual machine

Windows

Virtual machines

Cloud controller (CLC)

Eucalyptus

Cluster controller (CC) Cluster controller (CC)

Xen + VMGL + lustre Xen + VMGL + lustre

Open nebula Open nebula

Node A | Node B Node C | Node D

Openfiler iSCSI SAN servei (shared storage)

TCP/IP

Virtual machine I Linux I I Linux I

Xen package

Debian linux

Virtual machine Window"^ | Linux

ESX/ESXi server

ESX/ESXi package

Redhat linux kernel

Virtual machine cloud controller (CLC)+ cluster controller (CC) Hadoop package /N V Virtual machine node controller (NC)

Hadoop package Hadoop package Hadoop package

Linux Linux Linux Linux

VMware workstation

Ubuntu desktop

Figure 6: Virtual server in cloud and a shared storage with Openfiler.

Table 2: Cost affected by VM density and performance composite index ratio.

VM density (workload counts)

Performance composite index ratio

Capital expenditure

Client HW + MS VDA M

Server HW ✓

Storage HW M

Networking and security HW ✓

Hypervisor SW + SnS ✓ Operational expenditure

Infrastructure admin ✓

Power and cooling ✓

Rack space and office spacs ✓

Services + Training M Business agility

Planned downtime M

Unplanned downtime M

Business downtime ✓

Other + Tax ✓

M M M M M

Composite index

ale 2000

% 1500

eul 1000

V 500 0

VMware MS Hyper-V Proxmox Ubuntu CentOS Xen ESX R2 VE KVM

Hypervisor

VM composite index - Storage-accessing speed composite index Composite index

Figure 7: Composite index distribution.

part based on the ratio of ESXi normalized composite index to alternative one (i.e., minor part of estimation). In the experiment, we have deployed up to 50, 100, 150, 200, 250, and 300 workloads for the transition to their respective server virtualization with a 5-year duration. A summary of TCO/ROI calculation for 5 years is shown in Figures 9 and 10 in server virtualization as well as Figures 11 and 12 in desktop virtualization.

5.4. Cost Estimation for Server/Desktop Virtualization. According to the cost formula on (9), this part gives the operation cost for server/desktop virtualization so that the ratio of cost to performance (C/P ratio) for various virtual machine managements (hypervisors) is able to carry out the goal of the assessment in this paper. With a basis cost

Normalized composite index *

VMware MS Hyper-V Proxmox Ubuntu CentOS Xen ESX R2 VE KVM

Hypervisor

—♦— Normalized VM composite index —■— Normalized storage-accessing speed composite index —A— Normalized composite index

Figure 8: Normalized composite index distribution.

TCO (duration: five years)

D5000 US 4000 3000 2000 1000 0

150 200 Workloads

Hypervisor

■ VMware ESX

■ MS Hyper-V R2

■ Proxmox VE

Ubuntu KVM CentOS Xen

Figure 9: TCO histogram of server consolidation.

of vSphere ESX server indicated in (9), the operation cost computation to Hyper-V R2, Proxmox virtual environment, Ubuntu KVM, and CentOS Xen are conducted to disclose the real assessment of virtual server/desktop infrastructure. In terms of VM performance as indicted in (7) and (8), the composite index presents how the function of VM and its related storage-accessing speed perform in the various hypervisors, and the results are shown in Figures 7 and 8 as well. As we can see in Figure 13, a Costhypervisor divides CI and yields the C/P ratio with varying coefficients a/^, and the summary is also listed in Table 6. Even though Hyper-V R2 gains the best performance, Proxmox VE obtains the best choice in this study due to the lowest C/P ratio.

5.5. Discussion. In terms of VM performance and its storage-accessing speed as shown in Figures 7 and 8, Hyper-V R2 gains the best performance overall because of the highest composite index. As shown in Figures 9 and 10 in the server virtualization, the best choice is to take 150 workloads with ESX server because this combination will achieve the highest ROI and the lowest TCO over the duration of 5 years. However, when we look at desktop virtualization as shown

Table 3: Comparison ofVM performance of hypervisor.

Hardware specification

Memory

Hard disk

Network card

Server

Shared storage

Intel(R) Core(TM) i7-2600 CPU 3.40 GHz x 2

Intel E5620 CPU 2.4 GHz * 1

ASint DDRIII 8G-1600 x 2

8 GB DDRIII RAM

Seagate Barracuda 7200 1TB

1TB SATA HDD

RTL8169SC B7C33A5 GB29 TAIWAN (TG-3269) RTL8169SC B7C33A5 GB29 TAIWAN (TG-3269)

Table 4: Comparison of VM performance of hypervisor.

VM performance Unix bench 5.1.3 Ubuntu CentOS Pass mark performance test 7.0 Win XP Win Server 2003 Win 7 Composite index Normalized composite index

ESXi 5.0 1540.7 1550.3 1026.4 1126.1 1108.8 1316.3 1

Hyper-V R2 1619 1629 1213.4 1328.3 1318.9 1455.4 1.11

Proxmox VE 1411.8 1427.3 1013.3 750.9 976.4 1166.7 0.89

KVM 1411 1427 730 688.4 902.7 1096.4 0.83

Xen 1094.6 1084.7 700 597 860.3 904.2 0.69

ROI (duration: five years)

150 200 Workloads

Hypervisor

■ VMware ESX

■ MS Hyper-V R2

■ Proxmox VE

Ubuntu KVM CentOS Xen

Figure 10: ROI histogram of server consolidation.

350 300 250 200 150 100 50 0

ROI (duration: five years)

150 200 Workloads

Hypervisor

■ VMware ESX

■ MS Hyper-V R2

■ Proxmox VE

Ubuntu KVM CentOS Xen

Figure 12: ROI histogram of desktop virtualization.

£ 1500 U

1000 500 0

TCO (duration: five years)

150 200 Workloads

Hypervisor

■ VMware ESX

■ MS Hyper-V R2

■ Proxmox VE

Ubuntu KVM CentOS Xen

Figure 11: TCO histogram of desktop virtualization.

C/P ratio of hypervisor

ESXi 5.0 Hyper-V R2 Proxmox VE KVM Hypervisor

-♦- C/P ratio (a = 0.5, ß = 0.5) C/P ratio (a = 0.2, ß = 0.8) -A— C/P ratio (a = 0.6, ß = 0.4)

Figure 13: C/P ratio ofhypervisor.

Table 5: Comparison of storage-accessing speed performance.

Storage-accessing speed performance

Timing cached reads (MB/sec)

Timing buffered disk reads (MB/sec)

Composite index

Normalized composite index

ESXi 5.0 Hyper-V R2 Proxmox VE KVM Xen

11007.21 10475.72 10287.88 10503.85 10160.47

11.16 9.33 9.98 9.75 9.55

2210.4 2102.6

2065.6 2108.6

2039.7

0.95 0.93 0.95 0.92

Table 6: C/P ratio of hypervisor (cost unit: US$).

Operation cost C/P ratio Operation cost C/P ratio Operation cost C/P ratio « = 0.5, ß = 0.5 « = 0.2, ß = 0.8 « = 0.6, ß = 0.4

Hypervisor Composite index

ESXi 5.0 Hyper-V R2 Proxmox VE KVM Xen

1517.8 1640.3

1423.5

1385.6 1228.6

12,667 8,656 3,560 3,718 4,373

8.3 5.3

2.5 2.7

12,667 6,449 1,896 2,149 3,197

8.3 3.9 1.3 1.6

12,667 9,391 4,115 4,241 4,765

8.3 5.7 2.9 3.1 3.9

in Figures 11 and 12, Proxmox VE outperforms the others to achieve the best ROI over a 5-year duration, even though its TCO is a little bit less than ESX's TCO. In addition, Proxmox VE would not only be the best choice to save the initial investment to own a virtual server infrastructure with better ROI in desktop virtualization, but it also obtains the lowest C/P ratio. This paper does not mention the security issue for virtual machines, which is related to access control [19] and cryptograph in VMs [20]. It can be explored in the further work.

6. Conclusions

The objective of this paper is to explore several critical issues of virtual server/desktop infrastructure such as server consolidation, virtualization performance, virtual machine density, total cost of ownership (TCO), and return on investments (ROI). Thus, this paper introduces five distinct well-known hypervisors installed in VSiC and has proceeded with an empirical analysis of server consolidation and desktop virtualization. As a result, even though ESX server gets the highest ROI and the lowest TCO in server virtualization and Hyper-V R2 gains the best performance over all, both of them cost too much; instead Proxmox VE would not only be the best choice to save the initial investment to own a virtual server infrastructure with better ROI in desktop virtualization, but also it obtains the lowest C/P ratio. We drew the conclusion that Proxmox VE outperforms the other hypervisors operating in the virtual server/desktop infrastructure.

Acknowledgment

This work is supported by the National Science Council, Taiwan, under Grant no. NSC 100-2221-E-390-011-MY3.

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