MIUI, Hammer, what exactly is a deep customization system?

Users look forward to: Smart router manufacturer pole routing has issued a Hiwifi OS, known as Linux and OpenWrt depth optimized operating system. Domestic terminal manufacturers seem to like the custom operating system, the early OMS system of China Mobile (Weibo), other Miui, Lenovo's music OS, Alibaba's Aliyun operating system, etc. What is a deep custom operating system? Why do domestic manufacturers like this? Tencent Technology: The custom operating system is relative to the native operating system, some open source operating systems, such as Linux and Android allow the end-user to use free, terminal manufacturers can make some changes on its basis to achieve some of their own purposes. Depending on the extent to which the operating system is modified, it can be divided into general customization and depth customization. Customizing a set of UI interfaces such as the general customization, the original system changes are very small, but also very easy to compatible with native applications. Some manufacturers have made changes to the deeper layers of the system. Mobile operating system can be divided into kernel layer, middle tier and application layer. Based on the Linux operating system to customize the system, the bottom is the kernel of the Linux system, the middle layer contains a Java virtual machine named Dalvik, the application layer is based on the original system modified to add a variety of applications. Each application runs on its own process, enjoying the exclusive instance assigned to it by the Dalvik virtual machine. The so-called depth customization, generally refers to the middle layer to make changes, is to modify some of the Dalvik virtual machine settings. For example, the OMS operating system integrates a large number of enhanced middleware to better support a variety of applications, not simply replicating an Android system. So why do vendors like customizing the operating system? Because the biggest feature of the operating system itself is not customization, is universal. and domestic manufacturers are unable to develop new operating systems, or try to research and development but not enough success, then the second, choose a customized operating system to compatible with the existing large number of applications in the market, while the appropriate modification to meet their own application integration needs, this choice is reasonable, to some extent, is inevitable. In fact, Google (Micro-bo) Android operating system is also based on the Linux open source operating system's core design of the deep custom operating system, but it is relatively large changes to the kernel part of the changes, so it can be said to be a set of independent operating system. Domestic manufacturers have also tried to do stand-alone operating systems, such as Aliyun. Although the Linux system kernel is also used, Alibaba has developed its own virtual machines and made a large change in the middleware level. This is why Alibaba claims that the Aliyun OS is independent of Android's independent operating system. But the Aliyun operating system is also compatible with Android's Dalvik, and that is why Google countered that the Aliyun OS was modified by an Android system that directly uses Android's operating environment, framework, and tools, not stand-alone operating systems. So Google accusesAliyun operating system plagiarism requires Aliyun to remain compatible with Android. In an effort to put pressure on Alibaba, Google said it would lift its co-operation with Alibaba's Android products and license its technology. Alibaba has had to postpone its original partnership with Acer. Google's deep customization attitude, though not explicitly opposed, does not support it, and it has made it clear that it must pass the compatibility test (CTS) of the operating system. The use of the Android logo on the device after the CTS test allows the device to be well compatible with a large number of applications in the software market. Deep customization based on Android must meet this requirement. Some manufacturers directly based on the Linux system customization, but generally need to be compatible with the application of Android, on the one hand, easy to developers of the application of migration, the construction of the ecosystem, on the other hand is to meet the operating system of the general requirements of the hard, because, who let domestic manufacturers can not develop a The presence of a large number of custom operating systems has created an Android fragmentation situation. Google does not want manufacturers to do so. But Android is also an Open-source operating system, and Google has been laissez-faire in terms of expanding Android's market share. This is one of the reasons why the Android system is more confusing. Android-based, deeply customized operating systems are subject to Google updates, and must be synchronized with Android, as Android updates are fast and unpredictable, and there are risks to deeply customized systems.