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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Towards Green Metrics Integration in the MEASURE Platform</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Alessandra Bagnato</string-name>
          <email>alessandra.bagnato@softeam.fr</email>
          <email>alessandra.bagnato@softeam.fr,</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jérôme Rocheteau</string-name>
          <email>jerome.rocheteau@icam.fr</email>
          <email>jerome.rocheteau@icam.fr,</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Institut Catholique d'Arts et Métiers</institution>
          ,
          <addr-line>35 av. du champ de Manoeuvres, Carquefou</addr-line>
          ,
          <country country="FR">France</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Softeam Research &amp; Development Division</institution>
          ,
          <addr-line>Paris</addr-line>
          ,
          <country country="FR">France</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>-Current approaches to measure software energy consumption rely on different measurement tools that are not integrated with the software development life-cycle phases. We develop a model-based design methodology in order to cope with this problem. This methodology is tooled by a processing platform and a development environment based on OMG's Structured Metrics Metamodel models. We apply the approach to three specific measures that correspond to green metrics and we explain how they fit with different software development phases.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>I. INTRODUCTION</title>
      <p>Measuring software engineering during the software
development life-cycle phases involves different tools that are
used by different teams within the same company or in
different ones. It lacks of global view, unified collect platform
and deep analysis that could allow cross decision making in
software development that may engender costs loss due to a
management decision longer time.</p>
      <p>
        OMG’s Structured Metrics Metamodel (SMM) specification
[
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] defines an extensible meta-model for representing and
exchanging software-related measurement information
concerning software assets (designs, implementations, operations, etc).
The MEASURE platform consists of a web application that
allows to deploy, configure, collect, compute, store, combine
and visualize measurements by execution of software measures
that may be defined according to the SMM specification. Such
a usage has been described in [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>We apply the previous tooling to green computing through
out green metrics design and implementation based on the
EMIT power measurement tool. Three SMM measures are
modelled and deployed onto the MEASURE platform.</p>
      <p>This short paper is structured as follows: The section II
presents the MEASURE platform. The section III presents the
deployed tooling for embedding and processing the previous
green metrics within the MEASURE platform. The section IV
illustrates the methodology for reusing green metrics across
software development projects that are drawn out from open
source project unit test suites.</p>
    </sec>
    <sec id="sec-2">
      <title>II. MEASURE PLATFORM</title>
      <p>
        The MEASURE Platform [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] is a tool dedicated to
measure, analyse, and visualise the metrics to extract and show
information of the software engineering processes. Implement
the tools for automatically measure software engineering
processes during the whole software lifecycle by executing
measures defined in SMM standard and extracted from a
catalogue of formal and platform-independent measurements.
1) Provide methodologies and tools which allow measure
tools provider to develop a catalogue of formal and
platform-independent measure.
2) Implement storage solution dedicated to measurements
resulting of measure execution in big data context.
3) Implement visualization tools to expose the extracted
results in an easy-readable fashion, so allowing a quick
understanding of the situation and the possible actions
that can be taken to improve the diverse stages of the
software lifecycle.
4) Implement an extended API which allows external
analysis tools to access to collected measurement and to
contextual data related the measurement collect process
itself.
      </p>
      <p>
        The platform activity is organised around its ability to collect
measurement by executing measures defined by the SMM
standard. SMM measures are auto-executable component,
implemented externally, which can be interrogated by the
platform to collect measurements. The Measure platform provides
services to host, configure and collect measures, storing
measurement, present and analyse them. These measures are first
defined in SMM standard using the Modelio modelling tool [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]
and its extension dedicated to SMM modelling [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. They are
packaged under an executable format as Measure Definition.
Next, measures are registered and stored on Measure platform
using the dedicated REST service or the Web user interface.
In order to initiate the collect of measurement, the next step
consists on defining instance of measure based on measure
definitions. A measure represents a generic data collection
algorithm that has to be instantiated and configured to be
applied on a specific context. For example, a measure which
collects data related to an SonarQube repository must be
configured by the URL of this repository. Next the Measure
Platform can start collecting measurement (data resulting of
the execution of an instantiated measure). Direct measures
collect data in physical world while the Derived Measures are
calculated using previously collected measurement as input.
Collected measurements are stored on a No SQL designed to
be able to process a very large amount of data. To collect
measurements, the direct measures can delegate the collect
work to existing Measure tool. Finally, stored measurements
are presented directly to the end user following a business
structured way by the Decision-making platform, a web
application which allows organising measures based on projects
/ software development phases and display its under various
forms of charts. The measurements can also be processed
by analysis tools to present consolidated results [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
The Measure platform [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] provides services to host,
configure and collect measures, storing measurement, present
and analyse them. These measures are first defined in SMM
standard using the Modelio modelling tool and its extension
dedicated to SMM modelling. They are packaged under an
executable format as Measure Definition . Next, measures are
registered and stored on Measure platform using the dedicated
REST service or the Web user interface. In order to initiate
the collect of measurement, the next step consists on defining
instance of measure based on measure definitions. A measure
represents a generic data collection algorithm that has to be
instantiated and configured to be applied on a specific context.
For example, a measure which collects data related to an SVN
repository must be configured by the URL of this repository.
Challenges for MEASURE:
1) Define green metrics and develop methods and tools for
automated, precise, and unbiased measurement.
2) Deploy and evaluate a set of dedicated metrics,
3) Deploy an infrastructure able to processing a large
volume of Measures provided by big models repository,
4) Integrate the Measure platform with existing quality and
project management tools already deploied and used in
existing development environment,
5) Integrating green metric tools into development
environments and processes.
6) Offer a synthetic view resulting of the analysis several
measures allowing a manager to extract key information
related to several development process.
7) Used advanced analysis techniques like forecasting and
automated recommendation system to help us to exploit
the monitoring data and define mitigations actions to
issues detected with the help of the Measure platform.
A. Modelio
      </p>
      <p>
        Modelio [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] is a Modeling Tool developed by Softeam
since January 2009 supporting and integrating all the latest
major modelling or methodology standards. Modelio is first
and foremost a UML modelling environment, supporting a
wide range of models and diagrams, and providing model
assistance and consistency checking features. BPMN support
is integrated with UML with Modelio combining Business
Process Modelling and Notation (BPMN) and UML support
in one tool, with dedicated diagrams to support business
process modelling. The Modelio SMM Module [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] is the
first building block of the MEASURE project tool chain.
The Modelio modeling tool, enabled with the SMM Module
is based on Modelio’s open source distribution to allow the
specification of all the MEASURE’s metrics for measuring
activities in different phases of software engineering. Within
the MEASURE project the metrics modelled are structured
according to five software engineering phases: specification,
design, implementation, testing and production. These metrics
define measures then deployed on the MEASURE platform for
measurement collect and analysis. The figure 2 illustrates the
Modelio Environement and the MEASURE library covering
all the phases of the software development lifecycle used in
the MEASURE Project [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. We concentrate in this paper
on the software engineering production phase and in particular
on green metrics.
      </p>
      <p>
        III. GREEN METRICS IN THE MEASURE PLATFORM
Three metrics are integrated into the MEASURE platform
about software energy consumption. The first metrics
corresponds to the energy efficiency of a software artifact with
respect to another one. It is defined as a SMM ratio measure [1,
§11.8] between two other measures and consists of a positive
version of the energy waste rate in [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. This metrics is
defined on the top of the two other metrics. The second one
corresponds to the energy consumption of a software artifact.
it is defined as a SMM collective measure [1, §11.2] with a
custom accumulator that corresponds to the trapezoidal rule.
The figure 3 illustrates the Energy measure. In fact, energy is
computed from power measurements during a given time-span.
Indeed, energy measures are related to a list of power measures
which are defined as SMM direct measures [1, §11.5] i.e.
whose measurements are directly provided by external tools.
Every SMM power measures are defined by a float value
that corresponds to the power. The figure 4 illustrates the
Power and TimeStamp measure. Such measures are also
timestamped such that it enables to compute the trapezoidal rule
of an list of power measures ordered by their time-stamps.
The SMM specification makes possible to relate measures to
software artifact by the means of the measurand attribute of
SMM measures [1, §7.4]. It corresponds to any element of a
MOF model [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] and then allows a model-based approach for
measuring software and software engineering features.
      </p>
      <p>The tool chain that provides support to the previous SMM
measures consists in several collaborative tools around the
MEASURE platform:
1) It starts with power-meters that broadcast measurements
for electric features – such as current (intensity), voltage
(tension), power, power factor, etc – to corresponding
topics on a messaging-queue broker.
2) The broker forwards such messages to a data processing
system called EMIT that stores such messages and
exposes them throughout HTTP web services.
3) The SMM power measure integrated in the MEASURE
platform continuouslyretrieves and stores messages that
only corresponds to power measurements of a given
power-meter thanks to the previous services. Instances
of this SMM power measure can be configured in setting
EMIT server location and in selecting the corresponding
topics. It retrieves all the messages from the last retrieval
time-stamp to the current time-stamp.
4) The SMM energy measure integrated in the MEASURE
platform continuously computes the energy consumption
from power measurements during a given time-span.
Instances of this SMM energy measure can be configured
in setting the duration in milliseconds for computing
the energy consumption and in selecting the underlying
SMM power measure.
5) The SMM energy-efficiency measure integrated in the
MEASURE platform continuously relates energy
measures whose measurands are the same MOF element.
Instances of this SMM energy-efficiency measure can be
configured in setting the qualified name of this element.
The figure 5 illustrates the data-flow between all these
instruments, tools and platforms.</p>
    </sec>
    <sec id="sec-3">
      <title>IV. MODEL-BASED METHODOLOGY</title>
      <p>This set of tools around the MEASURE platform enables
energy efficiency to be taken into account during several
software development phases. For instance, a basic use case
consists in monitoring energy consumption and/or power peaks
at run-time during software production phase. A second use
case consists in comparing energy consumption of similar
software components (same functionality same interface, same
contract, etc) while testing i.e. in evaluating their energy
efficiency one to each other during the validation phase. A third
use case would consist in building a knowledge base about
software energy consumption in order to help developers at
earlier phases (design or implementation). Such a knowledge
base would make possible to build static analysis methods on
source code or models such that developers could improve
their software without feedback from testing or monitoring.</p>
      <p>On the one hand, the last use case is the most difficult to
realize according to the lack of knowledge in the domain of
software energy consumption and the reliability of power
measurements over programming language primitive statements.
On the other hand, the first use case is the most easy to realize
as many tools already provide measurements and analysis
results that fulfill it. We are focusing on the second use case as
it corresponds to the combination of the MEASURE platform
(model-based and metrics-oriented software engineering) and
the set of EMIT tools (power measurements and energy
analysis). In fact, it allows developers to improve their source
code throughout their knowledge of the differences between
two revisions of a same unit test. For example, if the same
unit test consumes more (resp. less) energy from a revision r1
to a revision r2, this means that the source code involved in
this unit test is responsible for this increase (resp. decrease) of
energy consumption. In fact, we assume that the same unit test
in different revisions assess the same functionality uniformly.</p>
      <p>Such an approach about unit test energy consumption and
efficiency requires to deploy a twofold continuous integration
server both on the system under test and on another computer.
The system under test will compile the source code and
execute the unit tests whereas the other server will, on the one
hand, command the system under test to execute a given unit
test and, on the other hand, retrieve from the EMIT tool the
time-stamps of the unit test execution beginning and end. Then
energy efficiency can be computed by the means of the energy
analysis tool and integrated backwards into the MEASURE
platform in order to provide reports. Such an architecture and
a process closely correspond to those presented in [10, §4].</p>
    </sec>
    <sec id="sec-4">
      <title>V. CONCLUSION AND FUTURE WORK</title>
      <p>Software energy consumption has in fact mainly been
studied with respect to factors such as execution duration, CPU
load, RAM usage, network bandwidth, disk access, etc. The
MEASURE platform makes possible to easily relate software
energy consumption with other software metrics thanks to its
SMM measure integration support. However, the underlying
tooling architecture that makes such an integration that easy
are itself rather complex. In fact, this architecture relies on
dispatched tools and services that provide, collect and analyze
measurements. In the future months we plan to run
experiments over software source code repositories. The planned
experiments will aim at providing examples of the energy
efficiency measure between the same test units from different
source code revisions.</p>
      <p>MQTT
pub
sub</p>
    </sec>
    <sec id="sec-5">
      <title>MEASURE platform</title>
      <p>HTTP
MQTT
system under test
power-meter
MQTT broker</p>
    </sec>
    <sec id="sec-6">
      <title>EMIT tool energy analysis tool</title>
    </sec>
    <sec id="sec-7">
      <title>VI. ACKNOWLEDGMENT</title>
      <p>The research presented in this extended abstract is funded by
the ITEA3 Project no. 14009 called MEASURE (1st December
2015 and running till 31st August 2019).</p>
    </sec>
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