Software Process Improvement CMM

Transcription

1 Software Process Improvement CMM Marcello Visconti Departamento de Informática Universidad Técnica Federico Santa María Valparaíso, Chile Software Engineering Institute Founded by the Department of Defense (USA), at Carnegie Mellon University, in 1984 First director: Watts Humphrey Goal: to establish standards of excellence in software engineering and accelerate the transition of advanced technology and methods to practice

2 Software Engineering Institute Important result: Software Process Maturity Model - developed to evaluate the capabilities of a software organization and identify the most important improvement areas - considering the complete process of software development as a process that can be controled, measured and improved Software Engineering Institute In order to improve their capabilities, the software organizations must: understand the present state of their software process; develop a view of the desired process; establish a list of the improvement actions required, in priority order; produce a plan to achieve those actions; and commit the resorces to execute the plan Tool: maturity framework

3 SEI s maturity model 5 level model (presented in 1987) Each level establishes an intermediate set of goals to achieve the higher level of maturity The 5 maturity levels reasonably represent the historical phases of evolutionary improvement at real software organizations, represent an improvement measurement that is reasonable to reach from the previous level, suggest improvement goals and intermediate progress measurement, and make obvious a set of priorities of immediate improvement once the status of an organization with respect to the framework is known (Watts Humphrey) SEI s maturity model 5 levels > initial (ad hoc/chaotic) > repeatable (intuitive) > defined (qualitative) > managed (quantitative) > optimizing (feedback)

4 SEI s maturity model Initial level > lack of formal procedures, cost estimates, project plans, administration mechanisms to assure that the procedures are followed, illintegrated tools, non-existent change control, higher administration does not understand key issues SEI s maturity model Repeatable level > process dependent on the individuals, basic project control are established, strengths when facing similar work, high risk when facing new challenges, lacks an ordered framework for improvement

5 SEI s maturity model Defined level > process defined and institutionalized, existence of a Software Engineering Process Group (SEPG) established to lead improvement SEI s maturity model Managed level > process is measured, a minimum set of quality and productivity measurements established, a process database established with resources for analysis and maintenance

6 SEI s maturity model Optimizing level > improvements fed back to the process, data collection automated and used to identify weakest process elements, numerical evidence used to justify application of technology to critical tasks, rigorous cause analysis and defect prevention SEI s maturity model Assessment procedure: review of an organization software process developed by a professional team, on site, during a week approximately Main tool: questionnaire with 101 yes/no questions

7 SEI s maturity model Main criticisms > tool to assess defense contractors (USA) > score determination (maturity level) > final reports not detailed enough > level 1 is reached with no effort > question scalability > algorithm complexity > score determination inflexibility > yes/no responses > lack of clarity in levels 4 and 5 SEI s maturity model Suggestions > modify the evaluation method > de-emphasize maturity level (score) Answer > new model: CMM (Capability Maturity Model), in 1991

8 Capability Maturity Model (CMM) Decompose each maturity level in key process areas (KPA), key practices, and key indicators Key process areas: goals to be reached to get to a particular maturity level Key practices: procedures and activities that contribute to reach the goals Key indicators: help in the determination of goal satisfaction, they form the basis for assessment procedure CMM structure Maturity Levels Process Capability indicate contain Key Process Areas achieve organized by Goals Common Features address Implementation or Institutionalization describe contain Key Practices Infrastructure or Activities

9 Capability Maturity Model (CMM) Level 1 - KPA > none Capability Maturity Model (CMM) Level 2 - KPA > requirements management > software project planning > software project oversight and tracking > software subcontract management > software quality assurance > software configuration management

10 Capability Maturity Model (CMM) Level 3 - KPA > organizational process focus > organizational process definition > training program > integrated software administration > software product engineering > intergroup coordination > peer reviews Capability Maturity Model (CMM) Level 4 - KPA > process quantitative management > software quality management

11 Capability Maturity Model (CMM) Level 5 - KPA > defect prevention > management of technology change > management of process change Capability Maturity Model (CMM) De-emphasizes score (maturity level) out of an assessment - final product is now a profile of key process areas, indicating their level of satisfaction The maturity level is established as that in which all key process areas are satisfied continuosly

12 Capability Maturity Model (CMM) Development of CBA/IPI, CMM-based appraisal for internal process improvement It has emphasized identification of problems and improvement actions over the numerical score It lacks conclusive validation; preliminary data are favorable (high ROI) It has become a de facto standard in the software industry Capability Maturity Model (CMM) CMM version 1.0: initial release, CMM version 1.1: 1993, only version used CMM version 2: 1996, never used (conflict with development of CMMI) Framework hasn t changed, new versions improve the structure of key process areas, practices, indicators, and improve the questionnaire

13 3 dimensions of CMM Eyesight: ability to observe, to identify status and progress -- levels 1, 2, and 3 Foresight: ability to aim, to goals and objectives -- level 4 Insight: ability to improve, to take corrective actions, learn, and change -- level 5 CMM early results Study at Hughes Aircraft Software Engineering Division, Results of first assessment: level 2 Results of second assessment: solid level 3 First major study in SEI s validation effort

14 CMM early results Estimated costs > US$ in assessment > US$ in training program > 75 person-month effort Estimated benefits > US$ per year (savings) > better work conditions, motivation, performance CMM early results Study at Raytheon Equipment Division, Evolution from level 1 to level 3, going through level 2 Improvement generated savings of US$ in rework reduction, with an investment of US$ , and a return of investment of 7:1

15 CMM early results Other studies and results (early 90s) > Lockheed: study predicts that between levels 1 and level 5 quality increments can be 100 times, and productivity increments 10 times > Motorola USA: similar to Raytheon > Motorola India: directly to level 5 in 2 years, using level 3 process at Motorola USA as a base CMM early results 1991 > 59 sites > sites 81% at level 1 CMM 12% at level 2 CMM 7% at level 3 CMM 0% at level 4 CMM 0% at level 5 CMM

16 CMM early results 1996 > 477 sites > sites 69% at level 1 CMM 18% at level 2 CMM 11% at level 3 CMM 1.5% at level 4 CMM 0.4% at level 5 CMM State of the practice

17 State of the practice A recent case study: Northrop Grumman Electronics, 600+ software engineers Rated at level 2 (1987) and level 3 (1989) SPI annual cost: US$2 million Starting in 1996, two main goals > accelerate productivity gains > move to the use of product lines, architecture and systematic reuse Moved to level 4 by 2001 State of the practice Tangible benefits > accelerate productivity gains 20% annually, up from 10% anually cost avoidance: US$25 million annually > move to the use of product lines, architecture and systematic reuse savings: US$20 million annually extra cost: US$800K annual Estimated ROI - 15:1

18 CMM Projections USA: level 3 minimum established by Department of Defense for its contractors (10 years ago) Relation CMM - ISO 9000: CMM level 3 implies certification ISO 9001? and viceversa? CMM -> SW-CMM -> CMMI CMM family - extension to other areas CMM Family Software CMM (SW-CMM): construction of software products People CMM (P-CMM): development of human resources Software Acquisition CMM (SA-CMM): adquisition of products and software-intensive systems Trusted CMM (T-CMM): construction of highly reliable software products Systems Engineering CMM (SE-CMM): construction of products and delivery of services (focus: systems engineering) Integrated Product Development CMM (ipd-cmm): construction of products and delivery of services (focus: collaboration of all disciplines) CMM integration (CMMI)

19 CMMI CMM Integration Source models: SW-CMM V2C, SECM, IPD-CMM Design goals > integrate source models, eliminate inconsistencies, reduce duplication > assure consistency with ISO (SPICE) > support to introduce new disciplines as needs arise Developed in DoD sponsored collaboration between industry, US government, SEI SCAMPI - Standard CMMI Appraisal Method for Process Improvement - similar to CBA/IPI CMMI Benefits > integration of system engineering and software engineering for aditional productivity & quality gains > efficient, effective assessment and improvement across multiple process disciplines > a common, integrated vision of improvement for all elements of an organization > can be used for appraising processes as well as process improvement

20 CMMI One model, two representations (both include essentially the same information) > CMMI Staged maturity levels (1-5), each defined in terms of a number of process areas organizational characteristic > CMMI Continuous capability levels (0-5), for a process area or a set of process areas process or process area capability CMMI Maturity vs. Capability - concepts are similar, but process area capability deals with a set of processes relating to a single process area or specific practice, while organizational maturity pertains to a set of process areas across an organization

21 CMMI Selecting a representation > CMMI as a means, not done for its own sake CMMI and SPI should help people, projects, programs & organization > Business goals must guide also the goals that organizations have regarding CMMI > Advantages of continuous representation provides maximum flexibility for focusing on specific process areas according to business goals and objectives > Advantages of staged representation clear goals and proven path for process improvement facilitates comparison of different organizations a familiar model for CMM users