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							VGREEN: A SYSTEM FOR
ENERGY EFFICIENT
COMPUTING IN VIRTUALIZED
ENVIRONMENTS

Gaurav Dhiman UC San Diego, La Jolla, CA, USA
Giacomo Marchetti UC San Diego, La Jolla, CA, USA
Tajana Rosing UC San Diego, La Jolla, CA, USA

Keywords: Virtualization, Migration, Energy, Workload Characterization
About Publisher
• International Symposium on
 Low Power Electronics and
 Design 2009
 Proceedings of the 14th
 ACM/IEEE international
 symposium on Low power
 electronics and design

• ISLPED10:
• Omni Hotel, Downtown Austin,
  Texas USA
• August 18-20, 2010
 About Author 1st : Gaurav Dhiman
vGreen: a system for energy efficient computing in virtualized environmentsGaurav Dhiman,
Giacomo Marchetti, Tajana Rosing
August         ISLPED '09: Proceedings of the 14th ACM/IEEE international
2009           symposium on Low power electronics and design
PDRAM: a hybrid PRAM and DRAM main memory systemGaurav Dhiman, Raid Ayoub,
Tajana Rosing
July           DAC '09: Proceedings of the 46th Annual Design Automation
2009           Conference
System-level power management using online learningGaurav Dhiman, Tajana Šimunic
Rosing
May            IEEE Transactions on Computer-Aided Design of Integrated
2009           Circuits and Systems , Volume 28 Issue 5
Dynamic voltage frequency scaling for multi-tasking systems using online learningGaurav
Dhiman, Tajana Simunic Rosing
August         ISLPED '07: Proceedings of the 2007 international symposium on
2007           Low power electronics and design
Dynamic power management using machine learningGaurav Dhiman, Tajana Simunic
Rosing
Novemb         ICCAD '06: Proceedings of the 2006 IEEE/ACM international
er 2006        conference on Computer-aided design
 About Author 2nd : Giacomo Marchetti
vGreen: a system for energy efficient computing in virtualized
environmentsGaurav Dhiman, Giacomo Marchetti, Tajana Rosing
August ISLPED '09: Proceedings of the 14th ACM/IEEE
2009     international symposium on Low power electronics and
         design
Publisher: ACM
In this paper, we present vGreen, a multi-tiered software system
for energy efficient computing in virtualized environments. It
comprises of novel hierarchical metrics that capture power and
performance characteristics of virtual and physical machines, ...
Keywords: energy, migration, virtualization, workload
characterization
     About Author 3rd : Tajana Simunic Rosing
Utilizing predictors for efficient thermal management in multiprocessor SoCsAyse Kivilcim Coskun, Tajana Šimunic Rosing, Kenny C. Gross
October 2009                        IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems , Volume 28
                                    Issue 10
Temperature- and Cost-Aware Design of 3D Multiprocessor ArchitecturesAyse K. Coskun, Andrew B. Kahng, Tajana Simunic Rosing
August 2009                         DSD '09: Proceedings of the 2009 12th Euromicro Conference on Digital System Design, Architectures,
                                    Methods and Tools
Predict and act: dynamic thermal management for multi-core processorsRaid Zuhair Ayoub, Tajana Simunic Rosing
August 2009                         ISLPED '09: Proceedings of the 14th ACM/IEEE international symposium on Low power electronics and
                                    design
vGreen: a system for energy efficient computing in virtualized environmentsGaurav Dhiman, Giacomo Marchetti, Tajana Rosing
August 2009                         ISLPED '09: Proceedings of the 14th ACM/IEEE international symposium on Low power electronics and
                                    design
PDRAM: a hybrid PRAM and DRAM main memory systemGaurav Dhiman, Raid Ayoub, Tajana Rosing
July 2009                           DAC '09: Proceedings of the 46th Annual Design Automation Conference
Adapting task utility in externally triggered energy harvesting wireless sensing systemsJamie Bradley Steck, Tajana Simunic Rosing
June 2009                           INSS'09: Proceedings of the 6th international conference on Networked sensing systems
System-level power management using online learningGaurav Dhiman, Tajana Šimunic Rosing
May 2009                            IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems , Volume 28
                                    Issue 5
Proactive temperature balancing for low cost thermal management in MPSoCsAyse Kivilcim Coskun, Tajana Simunic Rosing, Kenny C. Gross
November 2008                       ICCAD '08: Proceedings of the 2008 IEEE/ACM International Conference on Computer-Aided Design

Static and dynamic temperature-aware scheduling for multiprocessor SoCsAyse Kivilcim Coskun, Tajana Šimunic Rosing, Keith A. Whisnant,
Kenny C. Gross
September 2008                IEEE Transactions on Very Large Scale Integration (VLSI) Systems , Volume 16 Issue 9

Proactive temperature management in MPSoCsAyse Kivilcim Coskun, Tajana Simunic Rosing, Kenny C. Gross
August 2008                 ISLPED '08: Proceeding of the 13th international symposium on Low power electronics and design




Temperature management in multiprocessor SoCs using online learningAyse Kivilcim Coskun, Tajana Simunic Rosing, Kenny C.
Gross
June 2008              DAC '08: Proceedings of the 45th annual Design Automation Conference
An analytical model for the upper bound on temperature differences on a chipShervin Sharifi, Tajana Simunic Rosing
May 2008                       GLSVLSI '08: Proceedings of the 18th ACM Great Lakes symposium on VLSI
Accurate Temperature Estimation for Efficient Thermal ManagementShervin Sharifi, ChunChen Liu, Tajana Simunic Rosing
March 2008                     ISQED '08: Proceedings of the 9th international symposium on Quality Electronic Design
 Bibliometrics: Downloads (6 Weeks): n/a, Downloads (12 Months): n/a, Citation Count: 1
Temperature-aware MPSoC scheduling for reducing hot spots and gradientsAyse Kivilcim Coskun, Tajana Simunic Rosing,
Keith A. Whisnant, Kenny C. Gross
January 2008     ASP-DAC '08: Proceedings of the 2008 Asia and South Pacific Design Automation Conference
Dynamic voltage frequency scaling for multi-tasking systems using online learningGaurav Dhiman, Tajana Simunic Rosing
August 2007      ISLPED '07: Proceedings of the 2007 international symposium on Low power electronics and design
Active sensing platform for wireless structural health monitoringD. Musiani, K. Lin, T. Simunic Rosing
April 2007       IPSN '07: Proceedings of the 6th international conference on Information processing in sensor
                 networks
Temperature aware task scheduling in MPSoCsAyse Kivilcim Coskun, Tajana Simunic Rosing, Keith Whisnant
April 2007       DATE '07: Proceedings of the conference on Design, automation and test in Europe
Power and reliability management of SoCsTajana Simunic Rosing, Kresimir Mihic, Giovanni De Micheli
April 2007       IEEE Transactions on Very Large Scale Integration (VLSI) Systems , Volume 15 Issue 4
Scheduling Data Delivery in Heterogeneous Wireless Sensor NetworksDaeseob Lim, Jaewook Shim, Tajana Simunic Rosing,
Tara Javidi
December 2006 ISM '06: Proceedings of the Eighth IEEE International Symposium on Multimedia
Dynamic power management using machine learningGaurav Dhiman, Tajana Simunic Rosing
November 2006 ICCAD '06: Proceedings of the 2006 IEEE/ACM international conference on Computer-aided design

A simulation methodology for reliability analysis in multi-core SoCsAyse K. Coskun, Tajana Simunic Rosing, Yusuf Leblebici,
Giovanni De Micheli
April 2006        GLSVLSI '06: Proceedings of the 16th ACM Great Lakes symposium on VLSI
Energy estimation of peripheral devices in embedded systemsOzgur Celebican, Tajana Simunic Rosing, Vincent J. Mooney,
III
April 2004        GLSVLSI '04: Proceedings of the 14th ACM Great Lakes symposium on VLSI
    Reference
• [1] VMware Dynamic Resource Scheduler,
    http://www.vmware.com/files/pdf/drs_datasheet.pdf.
•   [2] P. Barham, B. Dragovic, K. Fraser, S. Hand, T. Harris, A. Ho, R. Neugebauer, I. Pratt, and
    A. Warfield. Xen and the art of virtualization. In Proc. SOSP ’03.
•   [3] C. Bienia, S. Kumar, J. P. Singh, and K. Li. The PARSEC benchmark suite:
    characterization and architectural implications. In Proc. PACT ’08.
•   [4] N. Bobroff, A. Kochut, and K. Beaty. Dynamic placement of virtual machines for
    managing SLA violations. In Proc. International Symposium on Integrated Network
    Management ’07.
•   [5] C. Clark, K. Fraser, S. Hand, J. G. Hansen, E. Jul, C. Limpach, I. Pratt, and A. Warfield.
    Live migration of virtual machines. In Proc. NSDI’05.
•   [6] G. Dhiman and T. Rosing. System-level power management using online learning. IEEE
    Transactions on CAD’09.
•   [7] F. Hermenier, X. Lorca, J.-M. Menaud, G. Muller, and J. Lawall. Entropy: a
    consolidation manager for clusters. In Proc. VEE’09.
•   [8] C. Isci, G. Contreras, and M. Martonosi. Live, runtime phase monitoring and
    prediction on real systems with application to dynamic power management. In Proc.
    MICRO’06.
•   [9] R. Knauerhase, P. Brett, B. Hohlt, T. Li, and S. Hahn. Using OS observations to improve
    performance in multicore systems. IEEE Micro’08.
    Reference
• [10] M. McNett, D. Gupta, A. Vahdat, and G. M. Voelker. Usher: an extensible framework
    for managing custers of virtual machines. In Proc. LISA’07.
•   [11] A. Merkel and F. Bellosa. Balancing power consumption in multiprocessor systems.
    SIGOPS Oper. Syst. Rev. ’06.
•   [12] R. Nathuji and K. Schwan. VirtualPower: coordinated power management in
    virtualized enterprise systems. In Proc. SOSP ’07.
•   [13] D. Nurmi, R. Wolski, C. Grzegorczyk, G. Obertelli, S. Soman, L. Youseff, and D.
    Zagorodnov. The Eucalyptus open-source cloud-computing system. In Proceedings of
    Cloud Computing and Its Applications’08.
•   [14] R. Raghavendra, P. Ranganathan, V. Talwar, Z. Wang, and X. Zhu. No "power"
    struggles: coordinated multi-level power management for the data center. In Proc
    ASPLOS’08.
•   [15] P. Ranganathan, P. Leech, D. Irwin, and J. Chase. Ensemble-level power management
    for dense blade servers. In Proc. ISCA ’06.
•   [16] A. Snavely and D. M. Tullsen. Symbiotic job scheduling for a simultaneous
    mutlithreading processor. In Proc. ASPLOS’00.
•   [17] A. Verma, P. Ahuja, and A. Neogi. Power-aware dynamic placement of HPC
    applications. In ICS ’08.
•   [18] T. Wood, P. J. Shenoy, A. Venkataramani, and M. S. Yousif. Black-box and gray-box
    strategies for virtual machine migration. In Proc. NSDI’07.
Cited by
• Addressing shared resource contention in multicore processors via
    scheduling
    S Zhuravlev, S Blagodurov, A Fedorova - ACM SIGPLAN Notices, 2010 -
    portal.acm.org
•   Gentlecool: Cooling aware proactive workload scheduling in multi-machine
    systems
    R Ayoub, S Sharifi, TS Rosing - Proceedings of DATE 2010 - seelab.ucsd.edu
•   PowerTracer: Tracing requests in multi-tier services to save cluster power
    consumption
    L Yuan, J Zhan, B Sang, L Wang, H Wang - Arxiv preprint arXiv: …, 2010 -
    arxiv.org
•   A system for online power prediction in virtualized environments using
    Gaussian mixture models
    G Dhiman, K Mihic, T Rosing - Proceedings of the 47th Design …, 2010 -
    portal.acm.org
•   Resource-conscious scheduling for energy efficiency on multicore processors
    A Merkel, J Stoess, F Bellosa - … of the 5th European conference on …,
    2010 - portal.acm.org
Motivation
• Power consumption is a critical design parameter in
  modern data center and enterprise environments
• Modern data centers use virtualization to get better fault
  and performance isolation, improved system
  manageability and reduced infrastructure cost through
  resource consolidation and live migration
• However, as we show later on, based on the utilization
  levels and characteristics of these different co-located
  VMs, the overall power consumption and performance of
  the VMs can vary a lot.
Introduction
• vGreen, a multi-tiered software system to manage VM
  scheduling across different PMs with the objective of
  managing the overall energy efficiency and performance.
• to understand and exploit the relationship between the
  architectural characteristics of a VM and its
  performance and power consumption.
• We implemented vGreen on a testbed of servers running
  Xen as the virtualization software.
• We show that vGreen is able to dynamically characterize
  and accordingly schedule the VMs across the PM cluster,
  improving the overall performance and energy efficiency
  by 20% and 15% respectively compared to state of the
  art VM scheduling policies.
Related Works
1.   Eucalyptus[13] and Usher[10], open source systems, managing VM
     creation and allocation across a PM cluster. Have no VM scheduling
     policies to dynamically consolidate or redistribute VMs.
2.   In [18], a VM scheduling system, which dynamically schedules the
     VMs across the PMs based on their CPU, memory and network
     utilization. Focusing on better overall performance.
3.   The Distributed resource scheduler (DRS) from VMware [1], a
     proprietary solution, also uses VM scheduling to perform automated
     load balancing in response to CPU and memory pressure.
4.   in [4], the authors propose VM scheduling algorithms for dynamic
     consolidation and redistribution of VMs for managing performance and
     SLA violations.
5.   in [7] propose Entropy, which uses constraint programming to
     determine a globally optimal solution for VM scheduling in contrast to
     the first fit decreasing heuristic used by [18, 4], which can result in
     globally sub-optimal placement of VMs.

•    none of these VM scheduling algorithms take into account the impact
     of the policy decisions on the energy consumption in the system.
Related Works
1.   In [12], the authors propose VirtualPower, uses the power
     management decisions of the guest OS on virtual power states as
     hints to run local and global policies across the PMs. It relies on
     efficient power management policies in the guest OS(in which sensors
     are virtualized), and does no VM characterization at the hypervisor
     level.
2.   In [14], a co-ordinated multi-level solution for power management in
     data centers is proposed. The model uses power estimation (using
     power sensors) and workload utilization levels to drive VM placement
     and power management. However, the model and results are based
     on offline trace driven analysis and simulations.

•    both [12] and [14] do not consider VM’s architectural characteristics

•    In [17], the authors use VM characteristics like cache footprint and
     working set to drive power aware placement of VMs. But their study
     assumes an HPC application environment, where the VM
     characteristics are known in advance. Besides, their evaluation is
     based on simulations.
Primary contributions
1. a system for characterization of VMs in a virtualized
   environment based on novel hierarchical metrics that
   capture power and performance profiles of the VMs
2. online VM characterization to drive dynamic VM
   scheduling across a PM cluster for overall
   performance and energy efficiency for general
   purpose workloads.
3. implement the proposed system on a real life testbed
   and through extensive experiments and measurements
   highlight the benefits of the approach over existing
   state of the art VM scheduling systems
vGreen Design: Motivation
• To understand the co-
  relation between VM
                                Intel         Intel
  characteristics and these     Quad          Quad
  metrics we performed some    Xeon 8        Xeon 8
  offline experiments and       CPU           CPU
  analysis using benchmarks
  from SPEC-CPU 2000 suite,
  namely mcf and perl.
• While mcf has high memory   VM 4   VM 4   VM 4   VM 4
  accesses per cycle (MPC)    VPCU   VCPU   VPCU   VCPU
  and low instructions per
  cycle (IPC), perl has low
  MPC and high IPC.
Homogeneous ( ‘same’)

     Intel Quad                                    Intel Quad
    Xeon 8 CPU                                    Xeon 8 CPU

 VM 4                  VM 4                  VM 4                    VM 4
 VPCU                  VCPU                  VPCU                    VCPU

perl perl perl perl   perl perl perl perl   mcf   mcf   mcf   mcf   mcf   mcf   mcf   mcf
Heterogeneous (‘mixed’)

     Intel Quad                                      Intel Quad
    Xeon 8 CPU                                      Xeon 8 CPU

 VM 4                  VM 4                    VM 4                    VM 4
 VPCU                  VCPU                    VPCU                    VCPU

perl perl perl perl   mcf   mcf   mcf   mcf   mcf   mcf   mcf   mcf   perl perl perl perl
Results of motivation experiments
Conclusion of motivation experiments
• co-scheduling VMs with similar characteristics is not
  beneficial from energy efficiency and power consumption
  balance point of view at high utilization rates
• co-scheduling VMs with heterogeneous characteristics on
  the same PM is beneficial from both energy efficiency and
  performance point of view
vGreen Design: Architecture
vgnode
• vgnode: A vgnode refers to an
  individual PMin the cluster. Each
  vgnode has vGreen modules (vgxen
  and vgdom) installed on them.
• vgxen is a module compiled into Xen
  and is responsible for characterizing
  the running VMs.
• vgdom is to communicate with vgserv
Hierarchical Metrics in vGreen
• vgxen starts the
   CPU counters of that
   PCPU to count the
   following events:
1. Instructions Retired
   (INST)
2. Clock cycles (CLK)
3. Memory accesses
   (MEM).
 MPC (MEM/CLK)
 IPC (INST/CLK)
 Util (VCPU on PCPU)
• wMPCcur= MPC · util
• wIPCcur = IPC · util



Estimated wMPC:
vgserv
• vgserv: managing VM scheduling
  across the vgnode cluster.
• vgpolicy makes the scheduling
  decisions based on VM metrics from
  the vgnodes. The metrics of each VM
  are aggregated by the vgpolicy to
  construct the top level or node level
  metrics (nMPC, nIPC, nutil)
• vgpolicy runs its balancing algorithm
  periodically
Balancing Algorithm: MPC balance
• 1) MPC balance:
 This step ensures
 that nMPC is
 balanced across all
 the vgnodes in the
 system for better
 overall performance
 and energy efficiency
 across the cluster
Balancing Algorithm
• 2) IPC balance: This step ensures nIPC is balanced
  across the vgnodes for better balance of power
  consumption across the PMs. The algorithm is similar to
  MPC balance, but uses nIPC instead of nMPC.
• 3) Util balance: This step balances the utilization of
  vgnodes to ensure there are no overcommitted nodes in
  the system, if there are other underutilized vgnodes.
• 4) VM consolidation: If all the metrics in the prior three
  steps are balanced, then this step tries to consolidate low
  utilization VMs to generate idle vgnodes in the system,
  which could be then be moved into low power states.
Evaluation Platform

                                                                        Vgserv:
             vgnode1:                          vgnode2:                Core2Duo
      Intel Quad Xeon 8 CPU             Intel Quad Xeon 8 CPU           Desktop
             Xen3.3.1                          Xen3.3.1                  Linux
                                                                         2.6.23




                                                                      Pp_period = 5s
                                                                      Pup_period = 5s
                                                                      nMPCth = 0.02
                                                 VM 3        VM 4
 Dom0          VM1         VM2     Dom0
                                               4 VPCU      4 VPCU     nIPCth = 8
Xen-Linux    4 VPCU      4 VPCU   Xen-Linux
                                                512MB       512MB
 2.6.18      512MB       512MB     2.6.18
                                              benchmark   benchmark
Benchmarks Used




 PARSEC benchmarks are parallel and multi-
 threaded
 SPEC benchmarks are single threaded.

 Each VM consists of four instances (for SPEC) or
 four threads (for PARSEC) of the benchmark.
Compare to Eucalyptus (E+)
• Eucalyptus is an open source cloud computing system, that
  can manage VM creation and allocation across a cluster of
  PMs. The default Eucalyptus VM scheduler assigns VMs using
  a greedy policy, i.e. it allocates VMs to a PM until its resources
  (number of CPUs and memory) are full.
• However, this assignment is static, and it does not perform any
  dynamic VM migration based on actual PM utilization at
  runtime.
• For fair comparison, we augment the eucalyptus scheduler with
  the utilization metrics and utilization/consolidation algorithms
  proposed in the previous section, which allow it to
  redistribute/consolidate VMs dynamically at run-time.
• We refer to this enhanced scheduler as E+
Parameter of results: Energy savings
• 1) Energy savings: We estimate the energy reduction in
 executing each combination of VMs using vGreen over E+.
 This is calculated by measuring the total energy
 consumption for a VM combination with E+ and vGreen,
 and then taking their difference. Note, that the
 combinations may execute for different times with E+ and
 vGreen, and since we do not know the state of the system
 after the execution (could be active if there are more jobs,
 or be in sleep state if nothing to do), we only compare the
 energy consumed during active execution of each
 combination.
Parameter of results:
Weighted Speedup (WS)

• Talonei is the execution time of VMi when it runs alone on a
  PM, and Te+i and Tvgreeni are its execution time as part of a
  VM combination with E+ and vGreen respectively.
• we normalize Te+i and Tvgreeni against Talonei for each VM,
  and then take ratio of the sum of these normalized times
  across all the VMs in the combination
Parameter of results: Reduction in Power Imbalance

• 3) Reduction in Power Imbalance: We also estimate
 the%reduction in power imbalance in the system with
 vGreen due to IPC balancing compared to E+. We
 estimate this using %reduction in variance in power
 consumption of the two vgnodes. A high value for this
 metric indicates better power balance across the two
 vgnodes with vGreen.
What’s happening during balance
 vgnode1            vgnode2           • Initial configuration
VM1        VM2     VM 3       VM 4    • Vgserv detect MPC imbalance
MPC        MPC     IPC        IPC     • Migrate VM1 to vgnode2


 vgnode1            vgnode2
                                       • Vgserv detect IPC and
  VM2       VM 3     VM 4       VM1      utilization imbalance
  MPC        IPC     IPC       MPC     • Migrate VM3 to vgnode1

                                      • Final configuration
Homogeneous Workloads
• We also experimented with combination of VMs running
  homogeneous benchmarks. We did experiments for all
  the six benchmarks in Table 2, where all the fours VMs
  ran the same benchmark. We observed that in all the
  experiments, there was no possibility of rebalancing
  based on characteristics, since the MPC and IPC of the
  VMs were already balanced.
• Consequently, the results for all the three parameters
  were the same as that for E+ across all the experiments.
Overhead
• Negligible overhead in read and report counters.
• Negligible performance impact of live migrating.
Conclusion
• In this paper we presented vGreen, a system for energy
 efficient computing in virtualized environments. The key
 idea behind vGreen is linking workload characterization to
 VM scheduling decisions to achieve better performance,
 energy efficiency and power balance in the system. We
 designed novel hierarchical metrics to capture VM
 characteristics, and develop simple balancing policies to
 achieve the above mentioned benefits. We implemented
 vGreen on a real life testbed of state of the art server
 machines, and show with SPEC and PARSEC
 benchmarks, that it can achieve improvement in
 performance and system level energy savings by up to
 20% and 15% respectively over state of the art policies.
Insights
• Typically we classify applications as IO-consuming and
  CPU-consuming, while in this paper, all CPU-consuming
  benchmarks are divided into MPC( memory consuming )
  and IPC( instruction consuming ). MPC is also a kind of IO
  operation but is counted in CPU usage. Heterogeneous
  workloads placement can improve both efficiency and
  power reduction.
• Parameter collecting running as Xen modules
Compare vGreen with
what we are doing currently
             Common                                 Difference

• implemented in physical            • vGreen use network
  testbed                                communication between vgdom
                                         and vgserver while we use
• Manage and monitor VMs                 status files stored in NFS.
  running on PMs cluster             •   vGreen classify CPU-usage as
  • Creating VMs                         MPC and IPC while we do not
  • balancing using live migration   •   vGreen collect cpu-usage data
• Take both efficiency and power         from xen as modules, while we
                                         try to use application level utility
  consumption into consideration
                                     •   We make priority among VMs
• Server / client architecture           while vGreen treat all VMs
• Use CPU-consuming                      equally
  benchmarks                         •   We assign resource (currently
                                         CPU) among VMs while vGreen
• Consolidate after balancing            leave this work to Xen.

						
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