Method and device for processing content file in content delivery network

Abstract

The embodiment of the invention provides a method and a device for processing a content file in a content delivery network (CDN). The method comprises the following steps of: storing metadata information of the content file of a node of the CDN into a database; and after the node is expanded, generating target Hash distribution of the content file in the expanded node, migrating the content file which does not conform to the target Hash distribution according to the metadata information and the target Hash distribution, and updating the metadata information until the content file conforms to the target Hash distribution. According to the method and the device, the problem that after the node of the content distribution network is expanded, the node cannot operate normally due to the fact that the content file does not conform to Hash distribution is solved, and the effect of ensuring the reliability of the node after expansion is achieved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the communication field, and in particular, to a method and device for processing content files in a content distribution network. Background Art

[0002] The current content delivery network (CDN) system architecture generally divides nodes into edge nodes and central nodes, where edge nodes are responsible for caching hot content watched by users, while central nodes are responsible for persistent storage of hot or specific content on the Internet. Content publishing is the process of injecting external content files into central nodes, regional centers or edge nodes for storage. According to the content distribution strategy, content is cached to edge nodes to shorten the distance between service points and users. The nearby service not only reduces the difficulty of solving quality of service (QoS) problems, but also saves the bandwidth of the backbone network. In order to ensure the quality of service, central nodes or regional centers usually need to store massive content files, and edge nodes will also have a large number of hot content cache files, which puts high demands on the storage capacity of CDN. As the number of stored content files continues to increase, the remaining storage space of the entire node will continue to decrease, which poses a great challenge to the stability of the entire system. At this time, nodes usually need to solve the problem of insufficient storage space by horizontal expansion or vertical expansion, and the expanded nodes are bound to have storage imbalance problems, which are prone to cause problems such as hot spot aggregation, resulting in poor user experience and uneven system load. Summary of the invention

[0003] The embodiments of the present invention provide a method and device for processing content files in a content distribution network, so as to at least solve the problem that after the nodes of the content distribution network are expanded, the nodes cannot operate normally because the content files do not conform to the hash distribution.

[0004] According to one embodiment of the present invention, a method for processing content files in a content distribution network is provided, comprising: saving metadata information of content files of a node of a content distribution network CDN to a database; after the node is expanded, generating a target hash distribution of the content files in the expanded node, migrating content files that do not conform to the target hash distribution according to the metadata information and the target hash distribution, and updating the metadata information until the content files conform to the target hash distribution.

[0005] In an exemplary embodiment, content files that do not conform to the target hash distribution are migrated according to the metadata information and the target hash distribution, including: determining a target storage device for the content file according to the metadata information and the target hash distribution; determining whether the target storage device for the content file is the same as an original storage device for the content file, and if the target storage device is not the same as the original storage device, migrating the content file to the target storage device.

[0006] According to another embodiment of the present invention, there is provided a device for processing content files in a content distribution network, comprising: a storage module for saving metadata information of content files of nodes of a content distribution network CDN to a database; a migration module for generating, after the node is expanded, a target hash distribution of the content files in the expanded node, migrating content files that do not conform to the target hash distribution according to the metadata information and the target hash distribution, and updating the metadata information until the content files conform to the target hash distribution.

[0007] According to yet another embodiment of the present invention, a computer-readable storage medium is provided, in which a computer program is stored, wherein the computer program is configured to execute the steps of any one of the above method embodiments when run.

[0008] According to yet another embodiment of the present invention, there is provided an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0009] Through the present invention, since the metadata information of the content files of the content distribution network is saved before the expansion, after the expansion, in order to ensure that the nodes can still operate normally, the target hash distribution of the content files in the nodes after the expansion is first generated, and based on the metadata information and the target hash distribution, the content files that do not conform to the target hash distribution are migrated until all the content files conform to the hash distribution and the nodes can operate normally. Therefore, the problem that after the nodes of the content distribution network are expanded, the nodes cannot operate normally because the content files do not conform to the hash distribution can be solved, thereby achieving the effect of ensuring the reliability of the nodes after the expansion. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a hardware structure block diagram of a computer terminal of a method for processing content files in a content distribution network according to an embodiment of the present application;

[0011] Figure 2 is a flowchart of a method for processing content files in a content distribution network according to an embodiment of the present invention;

[0012] Figure 3 is a structural block diagram of a device for processing content files in a content distribution network according to an embodiment of the present invention;

[0013] Figure 4 is a structural block diagram of a device for processing content files in a content distribution network according to yet another embodiment of the present invention;

[0014] Figure 5 is a structural block diagram of a device for processing content files in a content distribution network according to another embodiment of the present invention;

[0015] Figure 6 is a structural block diagram of a device for processing content files in a content distribution network according to another embodiment of the present invention;

[0016] Figure 7 is a schematic diagram of a central node according to an embodiment of the present invention;

[0017] Figure 8 is a flowchart of a method for processing content files in a content distribution network according to yet another embodiment of the present invention. DETAILED DESCRIPTION

[0018] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings and in combination with the embodiments.

[0019] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0020] The following is a description of relevant terms in the embodiments of the present invention:

[0021] Content Delivery Network: A Content Delivery Network (CDN) is a distributed network consisting of multiple servers and data centers. Its purpose is to improve availability and performance by distributing services geographically close to users. A content delivery network can cache static content (such as images, videos, files, etc.) and can also transmit dynamic content (such as live broadcasts, real-time data, etc.). A content delivery network can speed up the loading time of websites, mobile applications, and streaming media, and improve user satisfaction.

[0022] Hash algorithm: A hash algorithm (hash) is a mathematical function that can convert any input data into a fixed-length output, called a hash or hash value. The hash algorithm is one-way, that is, the original data cannot be restored from the hash value.

[0023] High-performance database: A high-performance database (DB) is a database management system that can perform high-performance data query and management, quickly process large amounts of data and complex queries, and provide efficient information services.

[0024] The method embodiments provided in the embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Taking running on a computer terminal as an example, Figure 1 1 is a hardware structure block diagram of a computer terminal for a method of processing content files in a content distribution network according to an embodiment of the present invention. Figure 1 As shown, the computer terminal may include one or more ( Figure 1 Only one is shown in the figure) a processor 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data, wherein the above-mentioned computer terminal may also include a transmission device 106 and an input / output device 108 for communication functions. It can be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the above-mentioned computer terminal. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations are shown.

[0025] The memory 104 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the method for processing content files in a content distribution network in the embodiment of the present invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, that is, to implement the above method. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories may be connected to the computer terminal via a network. Examples of the above network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0026] The transmission device 106 is used to receive or send data via a network. The specific example of the above network may include a wireless network provided by a communication provider of a computer terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 can be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0027] In this embodiment, a method for processing content files in a content distribution network running on the above-mentioned computer terminal is provided. Figure 2 is a flow chart of a method for processing content files in a content distribution network according to an embodiment of the present invention. Figure 2 As shown, the process includes the following steps:

[0028] Step S202, saving metadata information of content files of nodes of the content delivery network CDN to a database;

[0029] Among them, the content distribution network is a distributed storage network composed of multiple servers, providing network acceleration services for users.

[0030] The database may be a high-performance database, which is a database management system that can quickly process large amounts of data and complex queries and provide efficient information services.

[0031] In step S202, the metadata information of the content file of the node of the CDN is saved to the database, including: saving the metadata information of the content file of the node of the CDN to the database of the scheduling management node of the node; wherein the metadata information includes: the provider, name, type, storage device information, size and creation time of the content file.

[0032] By saving various metadata information of content files, we prepare for the subsequent generation of target hash distribution and migration of content files.

[0033] Step S204, after the node is expanded, generate a target hash distribution of the content files in the expanded node, migrate the content files that do not conform to the target hash distribution according to the metadata information and the target hash distribution, and update the metadata information until the content files conform to the target hash distribution.

[0034] Before generating the target hash distribution of the content file in the expanded node in step 204, the method further includes: the scheduling management device of the expanded node receives a request for the content file and description information of the content file; and the scheduling management device locates the storage device of the content file by querying the metadata information according to the description information.

[0035] In step 204, the content files that do not conform to the target hash distribution are migrated according to the metadata information and the target hash distribution, and the metadata information is updated until the content files conform to the target hash distribution, and the method also includes: the scheduling management device of the expanded node receives a request for the content file and the description information of the content file; the scheduling management device locates the storage device of the content file through a hash algorithm according to the description information.

[0036] By mapping a key value (content file related information) to one of the multiple storage service devices according to a hash algorithm, the storage location of the content file is located.

[0037] In step S204, the target hash distribution of the content file in the expanded node is generated, including: generating the target hash distribution of the content file in the expanded node according to the metadata information and the storage or bandwidth weight information of the device of the expanded node.

[0038] In step S204, content files that do not conform to the target hash distribution are migrated according to the metadata information and the target hash distribution, including: determining the target storage device of the content file according to the metadata information and the target hash distribution; determining whether the target storage device of the content file is the same as the original storage device of the content file, and if the target storage device is not the same as the original storage device, migrating the content file to the target storage device.

[0039] In step S204, the node is expanded, including one of the following: the number of storage devices of the node is increased; the storage space of all or part of the storage devices of the node is increased.

[0040] In an exemplary embodiment, migrating the content file to the target storage device includes: the target storage device sends a request to receive the content file to a provider or a superior source station of the content file according to an instruction to receive the content file, and receives the content file; and the original storage device deletes the content file.

[0041] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for enabling a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present invention.

[0042] In this embodiment, a device for processing content files in a content distribution network is also provided, and the device is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made are not repeated. As used below, the term "module" can implement a combination of software and / or hardware for a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0043] Figure 3 is a structural block diagram of a device for processing content files in a content distribution network according to an embodiment of the present invention. Figure 3 As shown, the device includes a storage module 10 and a migration module 20.

[0044] A storage module 10, used to store metadata information of content files of nodes of a content delivery network CDN in a database;

[0045] The migration module 20 is used to generate a target hash distribution of the content files in the expanded node after the node is expanded, migrate the content files that do not conform to the target hash distribution according to the metadata information and the target hash distribution, and update the metadata information until the content files conform to the target hash distribution.

[0046] Figure 4 is a structural block diagram of a device for processing content files in a content distribution network according to yet another embodiment of the present invention. Figure 4 As shown, the device includes Figure 3 In addition to all the modules shown, the migration module 20 also includes:

[0047] A receiving unit 21, used for the scheduling management device of the expanded node to receive a request for the content file and description information of the content file;

[0048] The positioning unit 22 is used for the scheduling management device to locate the storage device of the content file by querying the metadata information according to the description information.

[0049] Figure 5 is a structural block diagram of a device for processing content files in a content distribution network according to another embodiment of the present invention. Figure 5 As shown, the device includes Figure 3 In addition to all the modules shown, the device further includes: a receiving module 30 and a positioning module 40.

[0050] A receiving module 30, used for the scheduling management device of the expanded node to receive a request for the content file and description information of the content file;

[0051] The positioning module 40 is used for the scheduling management device to locate the storage device of the content file according to the description information through a hash algorithm.

[0052] Figure 6 is a structural block diagram of a device for processing content files in a content distribution network according to another embodiment of the present invention. Figure 6 As shown, the device includes Figure 3 In addition to all the modules shown, the migration module also includes: a generation unit 23.

[0053] The generating unit 23 is used to generate the target hash distribution of the content file in the expanded node according to the metadata information and the storage or bandwidth weight information of the device of the expanded node.

[0054] It should be noted that the above modules can be implemented by software or hardware. For the latter, it can be implemented in the following ways, but not limited to: the above modules are all located in the same processor; or the above modules are located in different processors in any combination.

[0055] To facilitate the understanding of the technical solution provided by the present invention, a detailed description will be given below in conjunction with embodiments of specific scenarios.

[0056] Figure 7 is a schematic diagram of a central node according to an embodiment of the present invention, such as Figure 7 As shown, the central node includes: one or more scheduling management devices, one or more content storage service devices;

[0057] The scheduling management device manages the subordinate storage service devices, and the scheduling management device and the content storage service device can be selected to be co-located or separately located. The scheduling management device in the present invention needs to use a high-performance memory database module, and the database module has no special requirements for the technical selection. In the present invention, the scheduling management device needs to switch between hash mode and DB mode, and use hash algorithms and high-performance databases to locate content file distribution, respectively, to improve service stability and reliability when the content hash distribution state is destroyed after node expansion.

[0058] The storage service device is used to store content files injected into the central node by the content provider. The content files can be media files, image files, etc. The file injection task needs to be dispatched to each storage service device through the scheduling management device to save the files injected by the content provider into the file system.

[0059] The scheduling management equipment should collect information from subordinate storage service equipment on a regular basis to ensure real-time control of the storage space of subordinate nodes.

[0060] For edge cache service nodes, the architecture composition is similar to that of content center nodes. The difference is that they store content cached from the source rather than content injected by content providers.

[0061] Figure 8 FIG. 1 is a flowchart of a method for processing content files in a content distribution network according to another embodiment of the present invention. Taking a central node as an example, it illustrates how to process content files of the central node to achieve a smooth transition before and after the central node is expanded. Figure 8 As shown, the specific process is as follows:

[0062] Step S802, recording content metadata when the node is in hash mode;

[0063] Specifically, under normal conditions, the scheduling management device of the central node is in hash mode. At this time, when a user requests a content file, a storage service device in the central node will be calculated through a hash algorithm based on the file description information of the file, and the user will be redirected to the device, where the user will receive content file services.

[0064] Step S804: If the storage space is insufficient or the storage is unbalanced, perform horizontal expansion or vertical expansion;

[0065] Specifically, content providers will continue to inject content files, and the central node may have problems with storage imbalance or insufficient storage space. Since the files injected by the content provider need to be stored persistently and cannot be lost, horizontal expansion or vertical expansion is usually performed at this time. Horizontal expansion means increasing the number of storage service devices in the central node to increase the total storage space; vertical expansion means increasing the storage space of all or part of the devices in the central node, which can also achieve the purpose of increasing the total storage space.

[0066] Specifically, after the expansion occurs, the original hash distribution relationship of the entire central node is destroyed. Therefore, when the hash algorithm is used to locate the content requested by the user, a positioning error will occur. The conventional solution is to save a set of old hash weight information, use the weight information before the expansion to perform hash calculations when scheduling user services, and use the cutover tool to adjust the distribution of the current content of the entire central node. During this process, the expansion operation cannot be performed again. Therefore, the present invention proposes a method for using a high-performance database to store metadata in advance, and saves the metadata of all content files injected into this node, but uses a hash algorithm to select equipment during service scheduling to ensure high performance and low latency in scheduling.

[0067] Step S806, switch to DB mode and locate through metadata;

[0068] Specifically, the node is switched to the DB mode of the present invention for operation. The so-called DB mode means that the metadata information of the content is stored and managed regardless of whether it is injected or returned to the source to generate the cache. Since the previous hash distribution has been destroyed by the expansion action, the current content distribution relationship can no longer be calculated by the hash algorithm, so it is necessary to determine the device where the file is stored by querying the metadata. When using the DB mode for positioning services, first perform a metadata query on the content requested by the user. If the metadata information can be queried and obtained, the user can be directly redirected to the corresponding node service stored in the metadata; if the metadata information cannot be queried, a device is calculated according to the hash algorithm to dispatch the user. At this time, the entire service process has an additional memory database query process, so compared to the hash algorithm, its scheduling delay will increase, especially in high-concurrency scenarios, but it also ensures the accuracy and stability of content positioning scheduling at this time.

[0069] Step S808, node content is automatically balanced;

[0070] Specifically, after switching to DB mode, the node starts the background task and recalculates the hash distribution according to the metadata of the content and the storage or bandwidth weight information of the current device. If the calculation result is inconsistent with the metadata description, a migration task needs to be generated to migrate the content from the original device to the new device and update the metadata storage. The so-called migration task, for the central node and the edge media service node, is a content injection task and a cache injection task, respectively. The implementation method is to send a remote procedure call (RPC) instruction to the node device through the application layer protocol. The node device requests the content provider or the upper source station to obtain the specified content file and store it in the current device according to the instruction content. After completing the download or return to the source, it is necessary to synchronously generate the content deletion / cache deletion RPC instruction to the source data node to delete the original content and metadata to ensure data uniqueness.

[0071] Step S810, determining whether the node has reached a hash distribution steady state;

[0072] Specifically, the metadata is scanned to determine whether the node has reached a steady state of hash distribution. When the device recorded by the background task scanning metadata is consistent with the device calculated by the current weight information, we believe that the node has recovered to a steady state and jump to step S812; if there is still content that does not match the hash distribution, it is necessary to continue to generate migration tasks and jump to step S808 until the entire node is restored to the problem. During the entire process, task generation also needs to be flow-controlled to avoid affecting the node's running services.

[0073] Step S812: switch to using a hash algorithm to locate the content device.

[0074] Specifically, when the node returns to a steady state, it switches back to the hash algorithm for user service scheduling. During the entire content automatic balancing process, the metadata stored in the database is used for user service scheduling. Compared with the use of hash algorithm scheduling, although some delays are added, the reliability of the entire balancing process is greatly improved, and the problem of not being able to expand again during the previous expansion and balancing process is also solved.

[0075] An embodiment of the present invention further provides a computer-readable storage medium, in which a computer program is stored, wherein the computer program is configured to execute the steps of any of the above method embodiments when running.

[0076] In an exemplary embodiment, the computer-readable storage medium may include, but is not limited to, various media that can store computer programs, such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk.

[0077] An embodiment of the present invention further provides an electronic device, including a memory and a processor, wherein a computer program is stored in the memory, and the processor is configured to run the computer program to execute the steps in any one of the above method embodiments.

[0078] In an exemplary embodiment, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor, and the input / output device is connected to the processor.

[0079] For specific examples in this embodiment, reference may be made to the examples described in the above embodiments and exemplary implementation modes, and this embodiment will not be described in detail herein.

[0080] By using a hash algorithm plus a high-performance database model, the service and management process are separated. The content metadata is stored in a high-performance memory database to achieve accurate content positioning when the hash distribution relationship is destroyed after the entire node is expanded, effectively ensuring the reliability of the service during the expansion process. At the same time, by scanning the content metadata of the entire node, a migration task is generated for the content that does not conform to the hash distribution after expansion, and it is migrated to the home device to achieve automatic content balancing among servers within the same node. After the entire central node reaches a steady state, it switches back to the service mode of using the hash algorithm to locate the content to achieve a smooth transition and improve the user experience during the entire expansion process.

[0081] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for processing content files in a content distribution network, characterized in that: include: Saving metadata information of content files of nodes of content delivery network CDN to a database; After the node is expanded, a target hash distribution of the content files in the expanded node is generated, content files that do not conform to the target hash distribution are migrated according to the metadata information and the target hash distribution, and the metadata information is updated until the content files conform to the target hash distribution.

2. The method according to claim 1, characterized in that Before generating the target hash distribution of the content file in the expanded node, the method further includes: The scheduling management device of the expanded node receives a request for the content file and description information of the content file; The scheduling management device locates the storage device of the content file by querying the metadata information according to the description information.

3. The method according to claim 1, characterized in that Migrating the content files that do not conform to the target hash distribution according to the metadata information and the target hash distribution, and updating the metadata information until the content files conform to the target hash distribution, further comprising: The scheduling management device of the expanded node receives a request for the content file and description information of the content file; The scheduling management device locates the storage device of the content file through a hash algorithm according to the description information.

4. The method according to claim 1, characterized in that Generating the target hash distribution of the content file in the expanded node includes: The target hash distribution of the content file in the expanded node is generated according to the metadata information and the storage or bandwidth weight information of the device of the expanded node.

5. The method according to claim 1, characterized in that Migrating content files that do not conform to the target hash distribution according to the metadata information and the target hash distribution includes: Determining a target storage device for the content file according to the metadata information and the target hash distribution; It is determined whether the target storage device of the content file is the same as the original storage device of the content file; if the target storage device is not the same as the original storage device, the content file is migrated to the target storage device.

6. The method according to claim 5, characterized in that Migrating the content file to the target storage device includes: The target storage device sends a request to receive the content file to a provider of the content file or a superior source station according to an instruction to receive the content file, and receives the content file; The original storage device deletes the content file.

7. The method according to claim 1, characterized in that Saving the metadata information of the content file of the node of the CDN to the database includes: Saving the metadata information of the content file of the node of the CDN to the database of the scheduling management node of the node; The metadata information includes: the provider, name, type, storage device information, size and creation time of the content file.

8. The method according to claim 1, characterized in that The node is expanded, including one of the following: The number of storage devices of the node increases; The storage space of all or part of the storage devices of the node is increased.

9. A device for processing content files in a content distribution network, characterized in that: include: A storage module, used to store metadata information of content files of nodes of a content delivery network CDN in a database; A migration module is used to generate a target hash distribution of the content files in the expanded node after the node is expanded, migrate the content files that do not conform to the target hash distribution according to the metadata information and the target hash distribution, and update the metadata information until the content files conform to the target hash distribution.

10. The device according to claim 9, characterized in that The migration module also includes: A receiving unit, used for the scheduling management device of the expanded node to receive a request for the content file and description information of the content file; A positioning unit is used for the scheduling management device to locate the storage device of the content file by querying the metadata information according to the description information.

11. The device according to claim 9, characterized in that The device also includes: A receiving module, used for the scheduling management device of the expanded node to receive a request for the content file and description information of the content file; A positioning module is used for the scheduling management device to locate the storage device of the content file through a hash algorithm according to the description information.

12. The device according to claim 9, characterized in that The migration module also includes: A generating unit is used to generate the target hash distribution of the content file in the expanded node according to the metadata information and the storage or bandwidth weight information of the device of the expanded node.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, wherein the computer program implements the steps of the method described in any one of claims 1 to 8 when executed by a processor.

14. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method described in any one of claims 1 to 8 are implemented.

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