CN104503788A - Setting method capable of shortening starting time of Android operating system - Google Patents

Abstract

The invention discloses a setting method for shortening the startup time of an Android operating system, and belongs to the technical field of quick startup of an operating system. The present invention includes starting the Android device, executing the boot program, and loading the Linux kernel by the boot program; and then executing the Android user space resource loading, local service opening and user partition scanning, executing the Zygote process, and loading the Android virtual machine. After the resource, interrupt the process and set the restore point file for it, and create a restore point file inspection process, set the process to start after the bootloader loads the Linux kernel, to judge whether there is the restore point file, if it exists, then according to The restore point file restores the process of initializing the Android virtual machine; if it does not exist, then executes the process of initializing the Android virtual machine. The invention is used for Android devices, and can significantly shorten the system startup time under the premise of ensuring user experience.

Description

A setting method for shortening the startup time of the Android operating system

technical field

The invention relates to an operating system quick-start technology, in particular to a quick-start method based on an Android operating system.

Background technique

Android is a free and open-source operating system based on Linux. The Android operating system has been widely used in mobile devices, smart home appliances and other fields, such as smartphones, tablets, set-top boxes, and smart TVs. With the extensive use of the Android operating system in these fields, the slow system startup speed has become a shortcoming that many users complain about. Compared with devices such as mobile phones, which are less likely to be powered off and cold-started, tablet computers and smart TVs have a relatively high frequency of power-off cold-starts in actual use. Boot speed is an important factor affecting user experience.

The start-up process of the Android operating system is shown in Figure 1, and the sequence is as follows: bootloader, Linux kernel, local service, Android virtual machine, Android service, and application startup. It generally takes about 35 seconds for the Android operating system to enter the Android user interface from when the device is powered on, and it takes more than 28 seconds to start the user space: from the Zygote process (this process is used to initialize the Android virtual machine during the device boot process) ) is created until the SystemServer process (the process is used to manage Android system services) is created, it takes about 18 seconds; from the SystemServer process is created to the final access to the user interface, it takes about 10 seconds. The Zygote process completes the initialization of the Android virtual machine by preloading nearly 2,800 classes and resources such as icons, images, and strings, which consumes a lot of time. The time-consuming of the SystemServer process is to start the Android service and scan the installation package.

The current solution to shorten Android startup time is mainly based on ARM Hibernation (sleep/wake-up technology): all the data in the memory and the data of the running state of the CPU and the device are all saved in the memory space applied for by the solution, generating fast Start the memory image and save the memory image to the external memory (non-volatile storage device) in a specific format. After each startup of the device, the boot program will read the memory image in a specific format from the external memory to the memory and restore the CPU and device. operating status information. This method directly reads information from the backup image file and restores the operating state of the system, skipping the scanning stage of the latest system partition and user partition at each startup, so the user must do it again after each installation of a new application The system sleeps/wakes up to generate a memory image, otherwise the newly installed application will disappear after the device restarts, and this process takes a long time, which seriously affects the user experience.

Contents of the invention

The object of the present invention is to propose a setting method for shortening the startup time of the Android operating system in the user space, aiming at the problem of slow startup of the Android operating system and the shortcomings of existing related technical solutions.

In order to achieve the above object, the technical solution of the present invention is: improve the start-up process of existing initialization Android virtual machine process (Zygote process), its concrete realization comprises the following steps:

Step 1: Start the Android device, execute the boot program, and load the Linux kernel by the boot program; then perform Android user space resource loading, local service opening and user partition scanning;

Step 2: Execute the process of initializing the Android virtual machine, and after loading the classes and resources required by the Android virtual machine, interrupt the process of initializing the Android virtual machine;

Step 3: Create a restore point for the Zygote process: set the file directory of the restore point file (you can arbitrarily set the storage file directory), and create a restore point file under this file directory. The restore point file includes current process link information, process ID , CPU status information, memory execution environment information of the process;

Create a restore point file inspection process, set the restore point file inspection process to start after the bootloader loads the Linux kernel, and be used to judge whether there is the restore point file (that is, the user plays a role when starting the Android device), if it exists, then Restore the Zygote process according to the restore point file (that is, the Zygote process starts running at the restore point to skip the preloading stage of classes and resources, and complete the fast startup process); if it does not exist, execute the Zygote process based on the existing method .

The present invention creates restore points for the existing Zygote process, and only needs to find the corresponding restore point files to restore each time the system starts, avoiding repeated preloading class and resource operations when the system starts each time. Optimization can save about 14 seconds of system startup time. At the same time, since the present invention does not skip the scanning stage of the latest system partition and user partition each time it is started, the user does not need to rely on regenerating the memory image to ensure the existence of the newly installed application after the device is restarted, which makes up for the shortcomings of the existing solutions , improving the user experience.

Further, step 3 of the present invention also includes, after creating the restore point file, continue to execute the process of initializing the Android virtual machine, and judge whether the system can carry out the Android user interface, if not, then perform step 2, which is used to detect the backup Whether the Zygote process restore point file is successfully backed up.

In order to further shorten the system startup time, the present invention also includes delay loading package, delay start initial service setting:

The installation packages and services of the system partition are divided into delayed installation packages, delayed services and start-up installation packages, and start-up services (specifically, according to user demand surveys, we can select installation packages and services that are not commonly used by users or that will not be used by users immediately after system startup. As a delayed installation package, delayed service), the delayed installation package and service are moved from the system partition to the user partition; after the Android operating system is started, the delayed installation package and service are started.

The delay setting can be performed during any one of the above steps 1, 2 or 3 or after the above steps 1, 2 and 3 are completed. In the above settings, the non-essential installation packages and services are delayed loaded. This method can save about 5 seconds of startup time.

In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: the present invention has created a restore point to the Zygote process, and only needs to find the corresponding restore point file to restore when starting each time, avoiding the system Repeated preloading class and resource operations at the first startup, this optimization can save about 14 seconds of startup time. Secondly, the present invention performs delay loading operation on non-essential installation packages and services, and this method can save about 5 seconds of startup time. Finally, since the present invention does not skip the scanning stage of the latest system partition and user partition each time it is started, the user does not need to rely on regenerating the memory image to ensure the existence of the newly installed application after the device is restarted, which makes up for the shortcomings of the existing solutions , improving the user experience.

Description of drawings

The invention will be illustrated by way of example with reference to the accompanying drawings, in which:

FIG. 1 is a system architecture diagram when the Android operating system starts normally.

Fig. 2 is a flow chart of setting in Embodiment 1 of the present invention.

Detailed ways

In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the embodiments.

Example 1

Referring to Fig. 2, in order to realize shortening the startup time of the Android operating system, the present invention includes the following settings:

Step 101: Start the Android device, execute the boot program, and load the Linux kernel by the boot program; then perform Android user space resource loading, local service opening and user partition scanning, that is, complete system initialization based on the existing Android operating system.

Step 102: after the Zygote process has loaded the required classes and resources of the Android virtual machine, interrupt the Zygote process (the procr_freeze_process function provided by the library libprocr.so of the system (this function has a preprocessing check function) stops the interrupt clock and blocks the relevant signal to freeze the Zygote process)

Step 103:

(1) The function provided by the library libprocr.so completes the creation of the restore point for the Zygote process, that is, when the related functions provided by the library libprocr.so are called, the process will create a restore point for the Zygote process:

In this step, based on the obtained file structure of the current Android operating system file, write header information that can be recognized by the library libprocr.so for the restore point file (that is, set an identifier that can be recognized by the library libprocr.so for the restore point file ).

After the preload () function of Zygote process, add procr_request_check () library function, this function sends signal to kernel and makes Zygote process fall into kernel to create restore point file for oneself (restore point file is called Zygote.procr in the present embodiment); The file directory of the restore point file, in this embodiment, is set to/data/, then the current Zygote process link information, Zygote process ID, CPU state information, the memory execution environment information of the Zygote process, signal information (table header file, use To set the corresponding action of a certain signal) to the created restore point file;

(2) Create a restore point file inspection process (the present embodiment is named as the procr process), and set the procr process to start after the boot program loads the Linux kernel to determine whether there is a restore point file for the above settings under /data/, if there is , the Zygote process is restored according to the restore point file; otherwise, the Zygote process is executed based on the existing method.

In this embodiment, the setting of the procr process is specifically:

Write the file procr.sh: first check whether there is a process restore point file under /data/. If it exists, restore the Zygote process; otherwise, create a procr process, and the Zygote process is created by the procr process, and the Zygote process is executed based on the existing method.

Put the procr.sh file in the /system/bin directory and modify its permissions to be executable, and modify the init.rc script (the script records the functions executed by the initialization process) to make the system create the procr process before creating the Zygote process.

In this embodiment, when the Zygote process is restored according to the restore point file, the proc_restart program (/system/bin/proc_restart-f/data/Zygote.procr//recovery process state) of the procr process is based on the restore point file The content restores the Zygote process ID, CPU status information, and memory execution environment information of the Zygote process. Put proc_restart in the /system/bin directory and change it to executable permission, and save the restore file Zygote.procr in the /data directory with read-only permission. After the Zygote process returns to the runnable state, it continues to run at the restore point, thereby skipping the time-consuming preloading stage of classes and resources, and realizing the rapid startup of the system.

Step 104: the Zygote process completes the restore point creation, if the Zygote process continues to run and successfully enters the Android user interface at last to illustrate that the backup Zygote process restore point file is successful, otherwise enter step 102 to back up again;

In this step, the Zygote process returns to the procr process after completing the creation of the restore point, first turns on the stopped interrupt clock and then restores the blocked signal, and then continues to run the subsequent process (to enter the Android user interface) to test whether the Zygote process is backed up success.

For the Android device after the above settings, after starting the Android device, the user first executes the boot program, and the Linux kernel is loaded by the boot program, and after performing Android user space resource loading, local service opening and user partition scanning, the procr process is executed; Process procr can at first check whether there is a restore point file under /data/, if not, then recreate Zygote process by procr process and enter existing start-up mode; After restoring the running state, execute the follow-up process and enter the Android user interface), that is, continue to run at the restore point to skip the time-consuming preloading stage of classes and resources, and realize the rapid startup of the system.

Example 2

In the setting method of embodiment 1, settings about delaying installation packages and delaying services are added, specifically:

In step 101, the installation packages and services that are not commonly used by users or that will not be used by users immediately after system startup are selected according to the user demand survey, which are defined as delayed installation packages and delayed services, and the rest are defined as startup installation packages and startup services;

Then move the delayed installation package and delayed service from the system partition to the user partition, thereby temporarily blocking the init.rc script for unnecessary services (the script records the functions performed by the initialization process);

In this step, we take the blocking service A as an example to give a specific implementation manner. First, add code to the init.rc script:

On property: ro.user.start=1

Start A

In the init.rc script file, the action to be taken after a property is changed is recorded, and the execution condition of the action is given in the form of "onproperty:<key>=<value>". When a key value related to an execution condition is set, the trigger related to the condition will be triggered. As shown above, when the ro.user.start attribute value is set to 1, the A service will be started.

Finally, start the delayed installation package and service after the start of the Android operating system is complete. In this embodiment, use a customized Android application (named Delayinit.apk in this embodiment), select the user inactivity state to start the blocked service and install Packages for user partitions. In this step, add the customized Android application - Delayinit.apk to the system. After the system startup is complete, the Android Application Framework will send an Intent message to Delayinit.apk, named BOOTCOMPLETED Intent. Taking the above service A as an example, after receiving the intent message about service A, Delayinit.apk will select the user inactivity state, set the ro.user.start attribute to 1 and wake up the init process to start service A. When the user is in the inactivity state, Delayinit.apk will also call the "PM" tool to scan the installation package for installing the user partition. Described " PM " tool is provided by Android operating system, and it can call Package Manager system service implicitly to complete the scanning and installation work of installation package and service in specific partition (this embodiment is user partition).

The difference between the recovery Zygote process of the present invention and the existing dormancy/wake-up technology based on ARM Hibernation to a specific execution state is: the Zygote process returns to the restore point and starts running, only skipping the preloading stage of classes and resources and Updates that do not affect system applications, so the amount of information that needs to be restored is small and the restoration is rapid. However, the existing sleep/wake-up technology based on ARMHibernation will skip Android user space startup or even Linux kernel startup. Although the startup time of the skipped part is saved, the amount of information to be restored is large, and recovery is time-consuming. Restoring the backed-up image file results in failure to update system applications.

Using the method described in Embodiment 1, the process startup time information of normal startup and fast startup is collected through the BootChart tool. When starting normally, it takes about 18 seconds from the creation of the Zygote process to the loading of classes and resources; when starting quickly, it only takes about 4 seconds to complete this process.

Using the method described in Embodiment 2, the process startup time information of normal startup and fast startup is collected through the BootChart tool. When the delay technology is not used, it takes about 10 seconds from the creation of the SystemServer process to the final access to the user interface; after the delay technology is used, it only takes about 5 seconds to complete this process.

The present invention is not limited to the foregoing specific embodiments. The present invention extends to any new feature or any new combination disclosed in this specification, and any new method or process step or any new combination disclosed.

Claims (3)

1. shorten the method to set up of Android operation system start-up time, it is characterized in that, comprise the following steps:

Step 1: start Android device, performs boot, loads linux kernel by boot; Perform the loading of Android user's space resource again, local service is opened and user partition is scanned;

Step 2: perform initialization Android virtual machine process, after the class loaded needed for Android virtual machine and resource, interrupts initialization Android virtual machine process;

Step 3: the file directory that restoration point file is set, and restoration point file is created under described file directory, described restoration point file comprises the internal memory execution environment information of current process link information, process ID, CPU status information, process;

Create restoration point file checking process, arrange described restoration point file checking process to start after boot loads linux kernel, there is described restoration point file for judging whether, if exist, then according to restoration point file, initialization Android virtual machine process being reduced; If do not exist, then perform initialization Android virtual machine process.

2. the method for claim 1, is characterized in that, described step 3 also comprises, and after establishment restoration point file, continues to perform initialization Android virtual machine process, and judges whether system can carry out Android user interface, if not, then perform step 2.

3. method as claimed in claim 1 or 2, is characterized in that, also comprises and the installation kit of system partitioning and service are divided into delay installation kit, Delay Service and startup installation kit, startup service, delay installation kit and service are moved to user partition from system partitioning; After Android operation system has started, restart and postponed installation kit and service.