[Simh] [simh] performance monitoring in virtual machines

[Nelson H. F. Beebe]

The new article listed below appeared today, and may give some useful
ideas to those of you who are working with the innards of SIMH.

The article is available in PDF form from the DOI (Digital Object
Identifier) in the entry, but may require personal or library
membership for access.  Printed copies usually take 2 to 4 weeks to
arrive, so it may be awhile before your local academic library has the
journal issue.

@String{j-OPER-SYS-REV = "Operating Systems Review"}

@Article{Bratanov:2009:VMW,
  author =       "Stanislav Bratanov and Roman Belenov and Nikita
                 Manovich",
  title =        "Virtual machines: a whole new world for performance
                 analysis",
  journal =      j-OPER-SYS-REV,
  volume =       "43",
  number =       "2",
  pages =        "46--55",
  month =        apr,
  year =         "2009",
  CODEN =        "OSRED8",
  DOI =          "http://doi.acm.org/10.1145/1531793.1531802",
  ISSN =         "0163-5980",
  bibdate =      "Thu Apr 23 19:43:22 MDT 2009",
  bibsource =    "http://portal.acm.org/",
  abstract =     "This article addresses a problem of performance
                 monitoring inside virtual machines (VMs). It advocates
                 focused monitoring of particular virtualized programs,
                 explains the need for and the importance of such an
                 approach to performance monitoring in virtualized
                 execution environments, and emphasizes its benefits for
                 virtual machine manufacturers, virtual machine users
                 (mostly, software developers) and hardware (processor)
                 manufacturers. The article defines the problem of in-VM
                 performance monitoring as the ability to employ modern
                 methods and hardware performance monitoring
                 capabilities inside virtual machines to an extent
                 comparable with what is being done in real
                 environments. Unfortunately, there are numerous reasons
                 preventing us from achieving such an ambitious goal,
                 one of those reasons being the lack of support from
                 virtualization engines; that is why a novel method of
                 'cooperative' performance data collection is disclosed.
                 The method implies collection of performance data at
                 physical hardware and simultaneous tracking of software
                 states inside a virtual machine. Each statistically
                 visible execution point of the virtualized software may
                 then be associated with information on real hardware
                 events. The method effectively enables time-based
                 sampling of virtualized workloads combined with
                 hardware event counting, is applicable to unmodified,
                 commercially available virtual machines, and has
                 competitive precision and overhead. The practical
                 significance and value of the method are further
                 illustrated by studying a parallel workload and
                 uncovering virtualization-specific performance issues
                 of multithreaded programs.",
  acknowledgement = ack-nhfb,
  keywords =     "hardware performance event counters; virtual
                 machines",
}

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- Nelson H. F. Beebe                    Tel: +1 801 581 5254                  -
- University of Utah                    FAX: +1 801 581 4148                  -
- Department of Mathematics, 110 LCB    Internet e-mail: beebe at math.utah.edu  -
- 155 S 1400 E RM 233                       beebe at acm.org  beebe at computer.org -
- Salt Lake City, UT 84112-0090, USA    URL: http://www.math.utah.edu/~beebe/ -
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