Difficulties in the Perspective Software Development Process_PHP Tutorial

Author: Tian Zhanhai 1 Introduction If you are a programmer, you may often be troubled by being unable to complete tasks on time. If you are a project manager, you may find it difficult to develop software that meets budget and schedule requirements. In fact, software projects are often seriously overdue or over budget, which is still a problem that plagues most software organizations. According to a U.S. assessment report, among 17 major Department of Defense software contracts, the average 28-month schedule was delayed by 20 months. A task that should be completed in 4 years has not been submitted in 7 years, and not a single project has been completed on time. Deployment of the B1 bomber was delayed due to software problems, and the $58 billion A12 aircraft program was partially canceled for the same reason. Why has the software crisis that has lasted for 20 to 30 years gotten worse? Why is software development so difficult? This article attempts to analyze the difficulties of software development based on the author's experience and put forward some suggestions. 2 Difficulties 2.1 Great complexity Most large-scale software software products consist of dozens or even millions of lines of source code. For example, the Windows95 operating system consists of approximately 11 million lines of code. Each line of code may affect other parts of the program, and each part may affect each other. In such a complex and huge system, every small mistake may cause the entire system to collapse. Some large-scale software, such as Windows, may be one of the most complex things humans have ever built, and cannot be compared with the most complex buildings from ancient times to the present. 2.2 High degree of uncertainty There are many uncertain factors in a software project from the beginning. One: User needs are difficult to determine. This is because it is difficult for software developers to understand users’ needs in detail, and even users don’t know exactly what they need before seeing the product. Therefore, new needs may be raised from the beginning to the end of project development, causing the system structure to be constantly modified. Finally changed beyond recognition. Number two: Design isn’t entirely predictable. Sometimes, a solution that is considered feasible during design may not work when implemented, or the initial design solution has major flaws that were not discovered in time, or suddenly a technical difficulty that was not anticipated during design blocks the progress of the project. There is actually a lot of unpredictability from design to implementation. Third: User needs are constantly changing. If the initial user needs are not clearly understood, the entire project may soon be stuck in the changing needs and cannot extricate itself. Fourth: Uncertainty of objective conditions. During the progress of the project, there may be a flow of personnel, there may be an adjustment of resources, and there may be restrictions on objective conditions of one kind or another that block the normal progress of the project. Amid such high levels of uncertainty, it is not only difficult but even impossible to accurately estimate a project at an early stage. 3 Reasons for project delays 3.1 Over-optimism of developers Many developers tend to believe that everything will go smoothly. This kind of blind confidence is wrong for project development. According to the most optimistic estimates, most tasks may not be completed on time because there are too many uncertainties in software development. Without a clear understanding and estimate of the complexity and difficulty of the task, the time at one's disposal, and the interference of possible emergencies, even if one guarantees one's own schedule, delivery may often not be made on time. 3.2 Pressure from the outside As project managers or customers, they all hope that the project will end as soon as possible, so they set time nodes for the project. These time nodes may be set to be impossible or very difficult to implement, but developers have to work overtime in order to complete the work on time and complete the required functions as quickly as possible, and the consideration of the system structure will be put aside. Put it in a secondary position, thus laying hidden dangers for future program maintenance. What's even more frightening is that bugs will appear one after another as the pressure increases, eventually causing more rework. Programs are like programmers' children. Everyone wants their children to grow up strong, but there is no way. If you have more children and faster births, you cannot be eugenics. 3.3 Interference from things outside the project If the developers of a project are often interfered with and hampered by things outside the project and cannot devote themselves wholeheartedly to project development, the progress will often be affected. This phenomenon is more common in smaller software companies. A developer often wears multiple hats and even participates in the development of multiple projects at the same time. If other projects are rushed to completion, the project will have to be delayed. 3.4 Chaos in Project Management Chaos in project management within software companies seems to be a common problem worldwide. Carnegie Mellon University's Software Engineering Institute (SEI) has established a set of standards to measure the state of software companies from chaos to sustainable development. This is the CMM five-level standard. The first level is the most chaotic, and the situation gets better with each higher level. The fifth level is the best. By the end of January 2001, only 1,654 software companies and institutions in the world had passed various levels of certification.As can be seen from the figure below, this is a pyramid-shaped distribution state. The figure only shows second-level and above-level companies, and the number of first-level companies at the lowest level of the pyramid is 1,654! Therefore, from a global perspective, the overall level of software management is still very low. 3.5 Insufficient developers The competition for talents around the world may be most intense in the IT industry. On the one hand, the absolute shortage of talents has caused many companies to be unable to recruit the talents they urgently need; on the other hand, the flow of talents has also caused companies to easily lose their employees. If a project lacks manpower or talent moves frequently, normal progress of the project cannot be guaranteed. 4 How to avoid construction delays 4.1 Be fully prepared for uncertainty The Chinese are all very familiar with the Battle of Chibi in "Three Kingdoms Demonstration". Zhuge Liang laid several ambushes in Chibi to chase and intercept Cao Cao. If one move failed, there would be another one. In one move, the whole process was carefully prepared and deployed, so he won a great victory. The same is true for software development. In the early stages of the project, you should be prepared for various situations that may arise during the process, so as not to end up with nowhere to go. 4.2 Based on product flexibility Design flexibility is the soul of a software product. A good design is always easy to maintain and upgrade, but a bad design will cause a lot of trouble for future maintenance, and the entire product may even be scrapped and rebuilt. Therefore, in the early stages of software development, you should spend a lot of effort on the overall design, rather than rushing to code and cutting wood while sharpening your skills. The early investment will reap high returns. 4.1 Improve the level of software management The ISO9000 quality management system standard series is based on the premise that if there are no problems with the production and management system, then there will be no problems with the products and services provided. This shows how the management level is related to the quality of the products. crucial impact. I think the best way for a software company to improve its management level is to set a goal for itself, such as achieving CMM level certification or ISO9000 quality system certification. In the process of working towards these goals, it will gradually improve its management level. 1 Conclusion This article has made some superficial analysis of the difficulties in the software development process and the factors that often cause project delays, but it is not very systematic and comprehensive. Several suggestions were also made on how to avoid construction delays, and readers are kindly requested to criticize and correct them. 2 References 1. Carnegie Mellon University Software Engineering Institute. Software Capability Maturity Model (CMM): A Guide to Software Process Improvement. Electronic Industry Press, 2001.07. 2. [Germany] Hoch, Ledin, Puckett, Lindner, Miller. The secret of success in the software industry. Shanghai Far East Publishing House, 2000 3. Gong Jianya. Some theories and technologies of contemporary GIS. Wuhan University of Science and Technology of Surveying and Mapping Press, 1999.03 4. Liao Bin. Introduction to CMM 1. 2001.09

http://www.bkjia.com/PHPjc/509182.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/509182.htmlTechArticleAuthor: Tian Zhanhai 1 Introduction If you are a programmer, you may often worry about being unable to complete tasks on time. If you are a project manager, you may feel that development is on budget and on schedule...