Reliasoft offers software blocksim and training that address the topic of system maintainability. Last week, elsevier cut off thousands of scientists in germany and sweden from reading its recent journal articles, when negotiations over the cost of a nationwide openaccess agreement broke down. Developing maintainable software software sustainability. Maintainability index calculates an index value between 0 and 100 that represents the relative ease of maintaining the code. Ability of a computer program to be retained in its original form, and to be restored to that form in case of a failure. The maintainability index is calculated as a factored formula consisting of lines of code, cyclomatic complexity and halstead volume. Can we apply the maintainability index calculation formula.
Maintainability is an enabler for other quality characteristics. Plus, we back it up with our unmatched customer service. Empirical studies by others led to a series of variants, and calculation of the maintainability index. Mi is calculated as a factored formula consisting of lines of code loc, cyclomatic complexity ccand halstead volume hv. A software metric is a standard of measure of a degree to which a software system or process possesses some property. Relyence maintainability prediction bestinclass software. Refactoring and reengineering are practices to improve a software s maintainability. Maintainability index range and meaning code analysis. The maintainability index mi is a software maintainability model proposed by oman and hagemeister at the university of idaho 1991, originally presented at.
Software maintainability is defined as the ease with which a software system or a component can be modified, to correct faults, improve performance or other attributes, or adapt to a changed. An essential part of keeping a software s maintainability at a desired level or. Software maintainability means the ease with which a software system or component can be modified to correct faults, improve performance or other attributes or adapt to a changed environment. Think twice before using the maintainability index arie. Reliability, availability, and maintainability ram are three system attributes that are of tremendous interest to systems engineers, logisticians, and users. The tools calculate maintainability index for functions and classstruct definitions, for files and for the whole software. Apr 20, 2016 maintainability, or lack thereof, has significant business impact. Cqse blog why we dont use the software maintainability index. The software maintainability index mi is a singlevalue indicator for the maintainability of a software system. The mdemo would be implemented to continue reading. Different color codes are used to signify the maintainability index. How to effectively define and measure maintainability. Reliability, availability, and maintainability the mitre. Welker idaho national engineering and environmental laboratory.
An approach to find out at which maintainability metric. A high value of the maintainability index means better code maintainability. Both angles are discussed in the next two sections. Maintainability index is a software metric which measures how maintainable easy to support and. The software engineering institute promoted this alternate formula in their 1997 c4 software technology reference. This is a quick note about the maintainability index, a metric aimed at assessing software maintainability, as i recently run into developers and researchers who are still using it. Cqse blog why we dont use the software maintainability. This document is a first step towards the construction of a maintainability prediction model. The maintainability index is a combination of several metrics, including cyclomatic complexity and average lines of code, as well as computational complexity, based off the halstead volume function. The maintainability index mi is a software maintainability model proposed by oman and hagemeister at the university of idaho 1991, originally presented at the international conference on software maintenance icsm 1992 and later refined in a paper that appeared in ieee computer.
The maintainability index was introduced at the international conference on software maintenance in 1992. For this reason, many applications are replaced simply because the overhead to modify them becomes prohibitive. Maintainability is defined as the probability of performing a successful repair action within a given time. Can we apply the maintainability index calculation formula for the. In software engineering, these activities are known as software maintenance cf.
After nearly a decade of use, mi continues to provide valuable insight into soft. The cyclomatic complexity also affects other software metrics, like code maintainability index. For this purpose, software metric datasets of lucene, which is open source software of 163085 lines of code are used, and it is shown that the existing oman and hagemeister maintainability index mode model is not a good a predictor of maintainability. Calculate code metrics visual studio microsoft docs. Also consider and address software maintenance activity in the field as patches, upgrades, and new software revisions are deployed. Sep 03, 2011 a smaller number of statistical distributions is used for maintainability analysis than for reliability analysis. Chug, software maintainability prediction using machine learning algorithms, softw.
What is a good maintainability index using visual studio 2008. To date, it is included in visual studio since 2007, in the. Last week, elsevier cut off thousands of scientists in germany and sweden from reading its recent journal articles, when negotiations over the cost of a nationwide openaccess agreement broke down in these negotiations, universities are trying to change academic publishing, while publishers are defending the status quo. Since then, several papers have appeared critically discussing the index, the coefficient, the metrics it is composed of, and the difficulty of using it in practice. Maintainability, or lack thereof, has significant business impact. This is not a fixed industry set of rules, but rather a combination of them that works for the requirement of. Mi and minc maintainability index virtual machinery. Mission objectives include safety, mission success and sustainability criteria. Maintainability index is a software metric that indicates how maintainable easy to support and change the source code is. Look at fault detection and fault isolation fdfi coverage and the impact on repair time lines.
Measuring software maintainability is nontrivial and there exists no single metric to measure it accurately. The following list shows the code metrics results that visual studio calculates. The primary aim of the metric is to determine how easy it will be to maintain a particular body of code. The software maintainability index revisited citeseerx. The other model is the sig maintainability model, proposed by the software improvement group, where this thesis research was carried out.
Its objectives are to define the concept of maintainability, to describe the factors influencing it and to define criteria by which maintainability can be quantitatively. Software maintainability is defined as the degree to which an application is understood, repaired, or enhanced. The maintainability index is calculated as a factored formula consisting of lines. Various activities carried out during maintenance include the addition of new features, deletion of obsolete code, correction of errors, etc. Maintainability and flexibility at the software level are of predominant importance to drive innovation at the business process level. Relyence maintainability prediction provides the complete software tool you need for fully compliant milhdbk472 analyses, and includes the wealth of features found across the board in the relyence studio suite. Software maintenance is an expensive activity that consumes a major portion of the cost of the total project. Maintainability index with comments mi maintainability index which does not contain comments miwoc. Comparison of the sig maintainability model and the. This may be due to the fact that maintainability has traditionally lagged reliability theory in development. It identifies a set of software measures based on correlations published in empirical studies. Nov 20, 2007 the maintainability index has been reset to lie between 0 and 100. Welker maintainability index the combination of multiple metrics into a single indicator of relative maintainability of a body of source code was originally defined by oman and hagemeister.
Think twice before using the maintainability index arie van. To validate the method measuring maintainability index software mmis. Can we apply the maintainability index calculation formula for the objectoriented software. As both models aim to indicate maintainability, one would expect the outcomes of the two maintainability models to show a high degree of positive statistical correlation. Maintainability index maintainability index is a software metric which measures how maintainable easy to support and change the source code is. Look for opportunities to gather maintainability and testability data during all test phases. Software that is written without maintainability in mind requires about four times as much effort to maintain than it did to develop. Software maintainability free demo video explanation.
Developing maintainable software helps reduce technical debt. Abstractthe maintainability of the software system is becoming a very important characteristic due to growth in demand of quality software system. Based on the numbers given per method in the source code, one can easily tell if the code is complex or not. Reliability, availability, and maintainability sebok. This is a quick note about the maintainability index, a metric aimed at assessing software maintainability, as i recently run into developers and. The most commonly used distributions for maintainability analysis have been the normal, lognormal, and exponential. Bioinspired information and communications technologies, 2014. Sei maintanability index objectscriptquality cachequality. The maintainability index is computed by combining four traditional. How does visual studios calculate the maintainability index. The software metrics study was initiated to propose metrics of the maintainability of the software produced by the mdsf project. The maintainability index is calculated as a factored formula consisting of sloc source lines of code, cyclomatic complexity and halstead volume. Closely related concepts in the software engineering domain are evolvability, modifiability, technical debt, and code smells.
Comparative study of the factors that affect maintainability. Longitudinal evaluation of opensource software maintainability. A method can be complex but as long as there are unit tests for it, it is much simpler to maintain. Remediation cost development cost which can be restated as. However, existing definitions of maintainability, such as the halstead volume, mccabes cyclomatic complexity or the sei maintainability index provide a very poor understanding of what maintainability is how it.
Maintainability is a multifaceted quality attribute each of the facets must be analyzed to objectively measure it. Maintainability index range and meaning code analysis team blog. Maintainability demonstration mdemo is a formal process conducted by the product developer and the end customer to determine whether specific maintainability contractual requirements have been achieved i. The maintainability index is computed by combining four traditional metrics. A new maintainability index model is proposed with a new set of predictor metrics. Why we dont use the software maintainability index cqse blog. R syavasya department of computer science and engineering, gitam university visakhapatnam, andhra pradesh 530045, india abstract in this paper, we introduce a new process to obtain the maintenance cost by taking releaselevel model and retrieve. Software maintainability means the ease with which these operations can be carried out. We employ the maintainability index, technical debt ratio and a maintainability model based on the arisa compendium. Even if a metric is not a measurement metrics are functions, while measurements are the numbers obtained by the application of. Improving code quality with visual studio code metrics. You can upload the results of a local verification or remote verification. Code metrics maintainability index the ultimate visual. Typically, maintainability measures are validated using expert judgments about thestate of.
Writing elegant code and the maintainability index. Arie van deursen software engineering in theory and practice. Maintainability index is a software metric which measures how maintainable easy to support and change the source code is. Maintainability index is calculated with certain formulae from linesofcode measurement, mccabe and halstead measurement. Essentially, with cyclomatic complexity, higher numbers are bad and lower numbers are good. Observations as mentioned earlier, numerous papers have been written describing the successful application of mi as part of the software development process or within a software the software maintainability index revisited kurt d. The maintainability index is calculated with certain formulae from linesofcode measures, mccabe measures and halstead complexity measures. To have a good maintainability index in your code you should have a couple of metrics measured up. The maintainability index is not as much a fixed value you look at, its more of an indication that code is hard to understand, test andor debug. For more information, see generate code quality metrics.
The maintainability index is a value between 1 and 100. Collectively, they affect economic lifecycle costs of a system and its utility. This is not a fixed industry set of rules, but rather a combination of them that works for the requirement of your organization application and team. Software maintainability index revisited researchgate. Software maintainability is important because it is approximately 75% of the cost related to a project. In 1991 oman and hagemeister introduced a composite metric for quantifying software maintainability. Chug, application of evolutionary algorithms for software maintainability prediction using objectoriented metric, in 8th int. Maintainability index mi has been proposed to calculate a single number that expresses the maintainability of a system.
Mar 01, 2020 an important body of research exists linking these characteristics with software metrics, and proposing ways to automate quality assessment by aggregating software metric values into higherlevel quality models. A proposed new model for maintainability index of open. Maintainability index mi mi is a singlenumber value for estimating the relative maintainability of the code. It was proposed by oman and hagemeister in the early nineties 1. Maintainability index mi article cited from wikipedia maintainability index is a software metric which measures how maintainable easy to support and change the source code is. For information about how to generate code metrics data in visual studio, see how to. In this paper, we present a new method to find mi with respect to loc only. The history of the maintainability index goes back to 1992, and was included in visual studio in 2007. Color coded ratings can be used to quickly identify trouble spots in your code. This maintainability index mi has evolved into numerous variants and has been successfully applied to a number of industrial strength software systems. Typically, maintainability measures are validated using expert judgments about thestate of different systems and.
The maintainability index mi is a compound metric designed at the university of idaho in 1991 by oman and hagemeister. Ultimately the maintainability index is what works for your specific case. Think twice before using the maintainability index. Reliasoft offers software blocksim and training that address the topic of system maintainability analysis.
1151 745 1461 1162 558 1418 434 538 960 740 577 547 280 547 383 765 962 952 1064 673 1605 130 900 531 1401 735 1416 924 51 1489 800 1427 727 851 1425 1153 1203 1231 461 540 1087 139