Adaptive scheduling methods and systems for communication networks

Abstract

This disclosure provides an adaptive scheduling method and system for a communication network. The adaptive scheduling method includes: acquiring real-time data packets sent by a device to the communication network within a macro period; calculating the response processing time of the communication network to the real-time data packets; acquiring a period time sub-slice pre-allocated by the communication network to the device within the macro period, comparing the size of the period time sub-slice with the response processing time and calculating the difference between the two; and generating a corresponding time slice adjustment declaration message based on the difference and sending the time slice adjustment declaration message to the communication network, wherein the time slice adjustment declaration message carries time slice adjustment information.

Description

Technical Field

[0001] This disclosure relates to the field of industrial communication network technology, and in particular to an adaptive scheduling method and system for communication networks. Background Technology

[0002] EPA (Ethernet for Plant Automation) is a real-time Ethernet technology for control systems independently developed in China. It has been included in the international fieldbus standard IEC61158 and the real-time Ethernet standard IEC61784. Currently, EPA has been widely used in many fields such as power, chemical, machinery, mining, and petroleum.

[0003] The minimum communication cycle of an EPA communication network is called the communication macro cycle, which is further divided into periodic time and aperiodic time. In an EPA communication network, each device sends periodic data during the periodic time and aperiodic data during the aperiodic time. In a complex control system, there are both periodic and aperiodic messages, as well as high-priority triggered messages. The processing response time for high-priority triggered messages is usually required to be much shorter than the communication macro cycle.

[0004] To accommodate the communication requirements of the longest data frames when handling various types of real-time data communication, the device needs to be allocated a large time slice. Therefore, while the current EPA communication network scheduling method can guarantee the determinism of various message types, it cannot guarantee the real-time requirements of messages with processing response times much shorter than the communication macrocycle. In this case, the device suffers from severe bandwidth waste when transmitting short data frames (i.e., when the processing response time is short). Furthermore, when a single time slice cannot transmit multiple real-time data frames, the real-time performance of the data cannot be guaranteed. Summary of the Invention

[0005] To address the aforementioned problems, this disclosure provides an adaptive scheduling method and system for communication networks. By calculating the response processing required for real-time data packets and the periodic time slices pre-allocated by the communication network for real-time data packets, it can not only determine the difference between the periodic time slice and the response processing time, but also generate a corresponding time slice adjustment declaration message based on the difference. This facilitates corresponding time adjustments based on the generated time slice adjustment declaration message, thereby significantly improving the adaptability of communication network scheduling and solving the above problems.

[0006] According to a first aspect of this disclosure, an adaptive scheduling method for a communication network is provided, the adaptive scheduling method comprising: acquiring real-time data packets sent by a device to the communication network within a macro period; calculating the response processing time of the communication network to the real-time data packets; acquiring a period time sub-slice pre-allocated by the communication network to the device within the macro period; comparing the size of the period time sub-slice with the response processing time to calculate the difference between the period time sub-slice and the response processing time; and generating a corresponding time slice adjustment declaration message based on the calculated difference to send the time slice adjustment declaration message including time slice adjustment information to the communication network.

[0007] In one embodiment, the method further includes: broadcasting the time-slice adjustment declaration message to other devices in the communication network; and adjusting the real-time data packet transmission time of the other devices based on the time-slice information included in the time-slice adjustment declaration message.

[0008] In one embodiment, generating a corresponding time slice adjustment declaration message based on the calculated difference includes: in response to determining that the periodic time sub-slice is greater than the response processing time, generating a time slice adjustment declaration message including spare time slice information based on the difference; and in response to determining that the periodic time sub-slice is less than the response processing time, generating a time slice adjustment declaration message carrying additional time slice information based on the difference.

[0009] In one embodiment, the method further includes: after calculating the difference between the periodic time sub-slice and the response processing time, instead of generating a time slice adjustment declaration message, adding a corresponding time slice adjustment declaration field to the acquired real-time data message.

[0010] In one embodiment, the method further includes: determining whether there is a real-time data packet to be sent in the macro period of the device; in response to determining that there is a real-time data packet to be sent, determining the response processing time of the communication network for the real-time data packet to be sent; and in response to determining that the period time slice is greater than the response processing time and the difference is greater than the first response processing time, not generating a time slice adjustment declaration message but sending the real-time data packet to be sent in the device to the communication network.

[0011] In one embodiment, the method further includes: after sending the time-slot adjustment declaration message to the communication network, adjusting the periodic time and non-periodic time in the macro-cycle based on the time-slot information included in the time-slot adjustment declaration message; after adjusting the periodic time of the macro-cycle, determining whether the device has a real-time data packet to be sent in the macro-cycle; and in response to determining that the device has a real-time data packet to be sent, determining the transmission time of the real-time data packet to be sent based on the adjusted periodic time and the time-slot adjustment declaration.

[0012] In one embodiment, after the periodic time and aperiodic time of the macrocycle are adjusted, the macrocycle time is kept constant.

[0013] According to a second aspect of this disclosure, a system is provided for implementing the adaptive scheduling method according to the first aspect of this disclosure. The system includes: an acquisition module configured to acquire real-time data packets sent by a device to a communication network within the same macro period; a communication network unit configured to pre-allocate period time slices for the real-time data packets of the device; and a control unit configured to be communicatively connected to the acquisition module and the communication network unit, calculating the response processing time of the communication network to the real-time data packets and the difference between the period time slice and the response processing time; generating a corresponding time slice adjustment declaration message based on the difference, and sending the time slice adjustment declaration message to the communication network unit.

[0014] According to a third aspect of this disclosure, a computing device is provided for implementing adaptive scheduling of a communication network, the computing device comprising: one or more processors; and a memory storing computer-executable instructions, which, when executed by the one or more processors, cause the one or more processors to perform an adaptive scheduling method according to a first aspect of this disclosure.

[0015] According to a fourth aspect of this disclosure, a non-transient storage medium having computer-executable instructions stored thereon is provided, which, when executed by a computer, cause the computer to perform an adaptive scheduling method according to a first or third aspect of this disclosure.

[0016] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0017] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements.

[0018] Figure 1 A schematic diagram illustrating bandwidth waste in existing communication networks is shown.

[0019] Figure 2 A schematic diagram illustrating bandwidth waste in existing communication networks is shown.

[0020] Figure 3 A schematic diagram illustrating the lack of real-time performance in existing communication networks is shown.

[0021] Figure 4 A flowchart of an adaptive scheduling method for a communication network according to an embodiment of the present disclosure is shown.

[0022] Figure 5 A schematic diagram is shown of a time-slice adjustment message sent to a communication network according to an embodiment of the present disclosure.

[0023] Figure 6 A schematic diagram showing the real-time data transmission message transmission time and periodic time of the adjusted device 2 according to an embodiment of the present disclosure is shown.

[0024] Figure 7 A schematic diagram showing the real-time data transmission message transmission time and periodicity of the adjusted device 2 according to another embodiment of the present disclosure is shown.

[0025] Figure 8 A schematic diagram is shown of a time-slice adjustment message sent to a communication network according to an embodiment of the present disclosure.

[0026] Figure 9 A schematic diagram of a time-slice adjustment message sent to a communication network according to another embodiment of the present disclosure is shown. Detailed Implementation

[0027] The exemplary embodiments of this disclosure are described below with reference to the accompanying drawings, including various details of the embodiments to aid understanding, and should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this disclosure. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0028] The term "comprising" and its variations as used herein signify open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The terms "one example embodiment" and "one embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". Other explicit and implicit definitions may also be included below.

[0029] In the EPA communication network, devices transmit data according to a communication macro cycle, which is divided into periodic time and non-periodic time. Within the periodic time, each device is allocated a non-conflicting periodic time slice for transmitting real-time data. At the beginning of each allocated periodic time slice, each device in the EPA communication network sends a periodic message according to a preset configuration to transmit one frame of real-time data. As mentioned earlier, although the current scheduling method of the EPA communication network can guarantee the determinism of communication for various types of messages, when a device is handling multiple types of real-time data communication, a larger time slice needs to be allocated to that device to accommodate the communication requirements of the longest data frame.

[0030] In EPA communication networks, there may be situations where a device needs to transmit real-time data of varying lengths. When configuring the periodic time slices for this device, the periodic time slices must meet the requirements for transmitting real-time data packets carrying the longest payload data. For example, if a device needs to transmit two different lengths of real-time data, the periodic time slices allocated to that device must meet the requirements for real-time data packet communication carrying the long payload data. In this case, if... Figure 1 As shown, when the device needs to send real-time data packets carrying long payload data within macro cycle time 1, and needs to send real-time data packets carrying short payload or no payload data within macro cycle times 2 and 3, there is an idle time slice within the cycle time sub-slice allocated to it. The device suffers from serious time slice waste when transmitting real-time data packets carrying short or no payload data, resulting in bandwidth waste.

[0031] In another scenario, such as Figure 2 As shown, the macro-period time of the communication network is Tm, where the periodic time is Tp and the non-periodic time is Tnp. Device 1 and Device 2 send real-time data packets to the communication network within the periodic time of the communication network. The times when Device 1 and Device 2 send the real-time data packets are T0 and T1 respectively, and the communication network pre-allocates a certain number of periodic time slices for Device 1 and Device 2. (The rest of the text appears to be unrelated and possibly machine-generated.) Figure 2 As shown, when device 1 needs to send a real-time data packet carrying long payload data to the communication network in the first macro cycle and a real-time data packet carrying short payload data to the communication network in the second macro cycle, the device suffers from severe waste of cycle time segments when transmitting the real-time data packet carrying short payload data, resulting in bandwidth waste.

[0032] Furthermore, when a single time slice cannot transmit multiple real-time data packets, the real-time performance of the data packets cannot be guaranteed. For example... Figure 3As shown, the periodic time sub-slice allocated to device 1 is sufficient to send one real-time data message carrying a long payload, but it is insufficient to send both one real-time data message carrying a long payload and one real-time data message carrying a short payload. In this case, the real-time data message carrying the short payload needs to be delayed until the next macro-period. When real-time data communication requirements change, there is a problem where real-time performance cannot meet application needs.

[0033] Therefore, improving the adaptive scheduling capability of communication networks to enhance bandwidth utilization efficiency and ensure the real-time performance of real-time data packets has become a key consideration.

[0034] Based on the foregoing, this disclosure provides an improved adaptive scheduling method and system for communication networks. By calculating the response processing required for real-time data packets and the periodic time slices pre-allocated by the communication network for the real-time data packets, it can not only determine the difference between the periodic time slice and the response processing time, but also generate a corresponding time slice adjustment declaration message based on the difference. This facilitates corresponding time adjustments based on the generated time slice adjustment declaration message, thereby significantly improving the adaptability of communication network scheduling and solving the above problems. The adaptive scheduling method according to various embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. It should be understood that actual adaptive scheduling methods may involve other method steps, but to avoid obscuring the focus of this disclosure, these other method steps will not be discussed, and the accompanying drawings do not show them.

[0035] Figure 4 An adaptive scheduling method for a communication network according to some embodiments of the present disclosure is illustrated. For example... Figure 4 As shown, the adaptive scheduling method for a communication network provided in this disclosure includes: S1, acquiring real-time data packets sent by device 1 to the communication network within a macro period; S2, calculating the response processing time of the communication network to the real-time data packets; S3, acquiring the periodic time sub-slices pre-allocated by the communication network to the device within the macro period, comparing the size of the periodic time sub-slices with the response processing time and calculating the difference between the two; and S4, generating a corresponding time slice adjustment declaration message based on the difference, and sending the time slice adjustment declaration message to the communication network, wherein the time slice adjustment declaration message carries time slice adjustment information.

[0036] In step S3, generating the corresponding time slice adjustment declaration message based on the difference includes: when it is determined that the periodic time sub-slice is greater than the response processing time, generating a time slice adjustment declaration message carrying spare time slice information based on the difference; and when it is determined that the periodic time sub-slice is less than the response processing time, generating a time slice adjustment declaration message carrying additional time slice information based on the difference.

[0037] For example, such as Figure 5 As shown, after sending a real-time data packet carrying short payload data to communication network 1, device 1 immediately sends a time-slot adjustment declaration message to the communication network. The time-slot adjustment declaration message carries time information with an idle time slot length of Δt, indicating that there is an idle time slot of length Δt within the currently pre-allocated periodic time sub-slot of this device. This idle time slot can be used by other devices to transmit real-time data packets or to add non-periodic time within the current macro-period, thereby achieving the function of adaptive bandwidth adjustment of the communication network.

[0038] Optionally, after step S3, the adaptive scheduling method further includes: determining whether there is a real-time data packet to be sent in the macro period of device 1; when it is determined that there is a real-time data packet to be sent, calculating the first response processing time of the real-time data packet to be sent in the communication network; and when it is determined that the period time slice is greater than the response processing time and the time slice length Δt is greater than the first response processing time, not generating a time slice adjustment declaration message, but sending the real-time data packet to be sent by device 1 to the communication network.

[0039] When it is determined that device 1 does not have any real-time data packets to be sent during the macro cycle, the adaptive scheduling method further includes the following steps: broadcasting a time-slot adjustment declaration message to other devices (such as device 2), and adjusting the real-time data packet transmission time of other devices based on the time-slot information carried in the time-slot adjustment declaration message. For example, as... Figure 6 As shown, after receiving a time slice adjustment declaration message from device 1 carrying an idle time slice length of △t, device 2 adjusts the real-time data packet transmission time of device 2 within the current macro cycle time to T1', where T1' = T1 - △t.

[0040] Optionally, the adaptive scheduling method further includes: after sending a time-slot adjustment declaration message to the communication network, adjusting the periodic time and aperiodic time in the macro-period based on the time-slot information carried in the time-slot adjustment declaration message. For example... Figure 6 As shown, after sending a time slice adjustment declaration message carrying an idle time slice length of Δt to the communication network, the periodic time and aperiodic time within the current macro-period time are adjusted from Tp and Tnp to Tp' and Tnp', respectively, where Tp' = Tp - Δt and Tnp' = Tnp + Δt.

[0041] It is important to note that the adjustable Δt length should not exceed the aperiodic time length, and the original macro-periodic time remains unchanged after the adjustment of the macro-periodic and aperiodic times, thus ensuring deterministic scheduling of the communication network. If the adjustable Δt length exceeds the aperiodic time length, it may alter the macro-periodic time, thereby affecting the determinism of data transmission in the communication network.

[0042] Optionally, after adjusting the periodic time and aperiodic time of the macro cycle, the adaptive scheduling method further includes: determining whether there is a real-time data packet to be sent by device 1 in the macro cycle; when it is determined that there is a real-time data packet to be sent, calculating whether the spare time slice is greater than or equal to the response processing time required for the real-time data packet to be sent; and when it is determined that the spare time slice meets the response processing time required for the real-time data packet to be sent, sending the real-time data packet to be sent by the device to the communication network.

[0043] For example Figure 3 As shown, when device 1 needs to send one real-time data message carrying a long payload and one real-time data message carrying a short payload within the same macrocycle, the existing method will have real-time performance issues. In this case, as... Figure 7 As shown, to increase the pre-allocated periodic time slice length for device 1, a time slice adjustment declaration message with a time slice length of Δt is generated for the real-time data packets of device 1. After device 1 sends its first real-time data packet, it sends this time slice adjustment declaration message to the communication network, thereby adjusting the periodic time and aperiodic time in the communication network to Tp' and Tnp', respectively, where Tp' = Tp + Δt and Tnp' = Tnp - Δt. The time slice adjustment declaration message is also broadcast to device 2, informing device 2 that device 1 requires a periodic time slice of length Δt. Simultaneously, after receiving the time slice adjustment declaration message, device 2 adjusts its real-time data packet transmission time to T1', where T1' = T1 + Δt. In this way, device 1 and device 2 can send real-time data packets that need to be sent to the communication network within the same macro-period, thus ensuring the real-time performance of data transmission in the communication network.

[0044] Optionally, such as Figure 8 and 9 As shown, this adaptive scheduling method also includes calculating the difference between the periodic time sub-slice and the response processing time, and instead of generating a time slice adjustment declaration message, adding a corresponding time slice adjustment declaration field to the real-time data message. By adding a time slice adjustment declaration field to the original real-time data message, the communication network bandwidth occupied by the time adjustment declaration is effectively reduced.

[0045] Using the above method, this solution can adaptively adjust the bandwidth allocation of the communication network for real-time data packets carrying different payload data or frame lengths, thereby effectively improving the bandwidth utilization of the communication network while ensuring the determinism and real-time performance of the communication network.

[0046] This disclosure also provides a system for implementing the adaptive scheduling method according to any of the foregoing embodiments of this disclosure. The system includes: an acquisition module configured to acquire real-time data packets sent by a device to a communication network within the same macro period; a communication network unit configured to pre-allocate period time sub-slices for the real-time data packets of the device; and a control unit configured to be communicatively connected to the acquisition module and the communication network unit, calculate the response processing time of the communication network to the real-time data packets and the difference between the period time sub-slice and the response processing time; and generate a corresponding time slice adjustment declaration message based on the difference, and send the time slice adjustment declaration message to the communication network unit.

[0047] This disclosure also provides a computing device for implementing adaptive scheduling of a communication network, comprising one or more processors and a memory storing computer-executable instructions, which, when executed by the one or more processors, cause the one or more processors to perform an adaptive scheduling method according to any of the foregoing embodiments of this disclosure.

[0048] This disclosure also provides a non-transient storage medium having computer-executable instructions stored thereon, which, when executed by a computer, cause the computer to perform an adaptive scheduling method according to any of the foregoing embodiments of this disclosure.

[0049] Those skilled in the art will understand that this disclosure is not limited to the embodiments described above, and that it may be implemented in many other forms without departing from its spirit and scope. Therefore, the examples and embodiments shown are to be considered illustrative rather than restrictive, and various modifications and substitutions are permitted without departing from the spirit and scope of this disclosure as defined by the appended claims.

Claims

1. An adaptive scheduling method for communication networks, characterized in that, The method includes: Acquire real-time data packets sent by the device to the communication network within a macro cycle; Calculate the response processing time of the communication network to the real-time data packet; Obtain the periodic time sub-slices pre-allocated by the communication network to the device within the macro-period; Compare the period time sub-slice with the response processing time to calculate the difference between the period time sub-slice and the response processing time; and Based on the calculated difference, a corresponding time-slot adjustment declaration message is generated and sent to the communication network. This message includes time-slot adjustment information, such as the idle time-slot length. The periodic time within the current macro cycle is adjusted to the original periodic time minus the idle time-slot length, and the non-periodic time is adjusted to the original non-periodic time plus the idle time-slot length. After adjusting the periodic and non-periodic times of the macro cycle, the macro cycle time remains unchanged. The system determines whether the device has a real-time data packet to be sent within the macro cycle. If it is determined that a real-time data packet to be sent exists, the system calculates the first response processing time of the communication network for the real-time data packet to be sent. If it is determined that the cycle time slice is greater than the first response processing time and the time slice length is greater than the first response processing time, the system does not generate a time slice adjustment declaration message but instead sends the device's real-time data packet to be sent to the communication network. When it is determined that the device does not have any real-time data packets to be sent in the macro cycle, it broadcasts a time slice adjustment declaration message to other devices and adjusts the real-time data packet sending time of other devices based on the time slice information carried in the time slice adjustment declaration message.

2. The adaptive scheduling method according to claim 1, characterized in that, The time slice adjustment declaration message generated based on the calculated difference includes: In response to determining that the periodic time sub-slice is greater than the response processing time, a time slice adjustment declaration message including spare time slice information is generated based on the difference; and Corresponding to the determination that the periodic time sub-slice is less than the response processing time, a time slice adjustment declaration message carrying information on increasing the time slice is generated based on the difference.

3. The adaptive scheduling method according to claim 1, characterized in that, The method further includes: After calculating the difference between the periodic time slice and the response processing time, instead of generating a time slice adjustment declaration message, a corresponding time slice adjustment declaration field is added to the acquired real-time data message.

4. The adaptive scheduling method according to claim 1, characterized in that, The method further includes: After sending the time slice adjustment declaration message to the communication network, the periodic time and aperiodic time in the macro period are adjusted based on the time slice information included in the time slice adjustment declaration message; After adjusting the period time of the macro cycle, it is determined whether the device has any real-time data packets to be sent within the macro cycle; and In response to determining that the device has a real-time data packet to be sent, the transmission time of the real-time data packet to be sent is determined based on the adjusted period time and the time slice adjustment declaration.

5. A system for implementing the adaptive scheduling method according to any one of claims 1-4, characterized in that, The system includes: The acquisition module is configured to acquire real-time data packets sent by the device to the communication network within the same macro period; The communication network unit is configured to pre-allocate periodic time sub-slices of the real-time data packets of the device; and The control unit is configured to communicate with the acquisition module and the communication network unit, calculate the response processing time of the communication network to the real-time data packet and the difference between the periodic time slice and the response processing time, generate a corresponding time slice adjustment declaration message based on the difference, and send the time slice adjustment declaration message to the communication network unit.

6. A computing device for implementing adaptive scheduling in a communication network, characterized in that, The computing device includes: One or more processors; and A memory storing computer-executable instructions, which, when executed by the one or more processors, cause the one or more processors to perform the adaptive scheduling method according to any one of claims 1-4.

7. A non-transient storage medium having computer-executable instructions stored thereon, characterized in that, When the computer-executable instructions are executed by the computer, the computer causes the computer to perform the adaptive scheduling method according to any one of claims 1-4.

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