JPH05324497A - Real-time data processor - Google Patents

Abstract

PURPOSE:To guarantee the completion of data processing until the limit of processing completion. CONSTITUTION:A processing content number 10 transmitted from a processing request device 8 through a processing content number input latch 11 is stored in a storage means 2. At that time, processing request generating time is stored as well. The processing content number 10 outputted from the storage means 2 corresponding to an output instruction 71 of an executing means 7 is sent to a control means 6. At the same time, the processing request generating time outputted form the storage means 2 is sent to a subtracting means 3. At the subtracting means 3, the elapse of time after the processing request generating time is calculated by comparing it with the current time of a timer means 1 and compared with the processing margin time of a processing margin time detecting means 4 by a comparing means 5. When the passed time exceeds the processing margin time as this compared result, the data processing of the executing means 7 is stopped by the control means 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a real-time data processing apparatus which is related to an external process and performs a process according to a time requirement determined by the external process.

[0002]

2. Description of the Related Art A data processing device such as a computer may have to complete data processing within a predetermined time. For example, in a communication-related data processing device, if a packet in packet communication is not processed within a predetermined time, the packet is discarded or replaced with an appropriate one. That is, when the processing result is not obtained within the predetermined time from the generation of the processing request, the processing result is invalidated. Further, if the data of the processing request cannot be processed within the predetermined time, the processing is not necessarily executed or is treated as being obtained by other means. Here, the other means is, for example, a simple means that can be surely processed within a predetermined time.

Conventionally, in this type of device, when a processing request is received, the processing request is stored in a means or a device such as a FIFO (first in first out) or a ring buffer (cyclic queue). Then, a queue is created and held, and when the processing device becomes ready for processing, processing is performed in order from the oldest processing request. FIG. 2 is a time chart explaining a processing procedure in the conventional apparatus. This figure is an example in which (a) process request generation, (b) process execution, and (c) process completion deadline are shown on the time axis. (A) Regarding the processing request generation, first, the processing A request is generated (time t1), the processing B request is generated 0.25 msec thereafter (time t2), and thereafter, the processing C is performed at 1 msec intervals.
It is assumed that D and E occur.

(B) Regarding processing execution, each processing A,
Each of B, C, D and E requires 1 msec. Then, when the request for the process A is generated, the execution of the process A is started (time point t1), and immediately after the completion of the execution of the process A, the execution of the process B is started (time point t3). After that, process C,
D and E are continuously executed (time points t6, t9, t1
2). (C) Regarding the processing completion deadline, each processing A, B, C,
Both D and E must complete the processing within 1.25 msec from the generation of the processing request (time t).
4, t5, t8, t11, t13).

[0005]

However, the above-mentioned conventional techniques have the following problems. That is, in FIG. 2, the processing A starts to be executed at the same time as the processing request is generated (time t1), and is completed after 1 msec (time t3).
Therefore, the processing completion deadline (time t4) can be met. However, the processing B is started to be executed when 0.75 msec has elapsed from the generation of the processing request (time point t3) and is completed after 1 msec (time point t6). Therefore, the processing completion deadline (time t5) cannot be met. As a result, the process B is invalidated. After that, the processing C is also started when 0.75 msec has elapsed from the generation of the processing request (time t6), and is completed after 1 msec (time t9). Therefore, the processing completion deadline (time t8) cannot be met. As a result, the process C is also invalidated. Similarly, the processing D and E are also processing completion deadlines (time points t11 and t13).
It will be invalidated in time. Therefore, except for the process A,
There was a problem that all of them were invalidated and the actual processing capacity was significantly reduced.

The present invention has been made by paying attention to the above points. By eliminating unnecessary processing by not starting the processing which does not meet the processing completion deadline from the beginning, the substantial processing capacity is achieved. It is an object of the present invention to provide a real-time data processing device which is improved.

[0007]

The real-time data processing apparatus of the present invention comprises a clock means for outputting the current time, and a storage means for storing the requested processing and the request generation time output from the clock means at the request time. And subtraction means for subtracting the request generation time accumulated in the accumulating means from the current time output by the time measuring means to obtain the elapsed time from the request time, and the start of the processing for accumulating in the accumulating means. Processing margin time detecting means for detecting the margin time, comparing means for comparing the elapsed time output by the subtracting means and the margin time detected by the processing margin time detecting means, and the result of the comparison by the comparing means, Control means for controlling the processing accumulated in the accumulating means depending on whether or not the elapsed time exceeds the margin time, and the elapsed time is controlled by the control means. A predetermined data processing is executed when the time is within the time, and either the predetermined data processing is stopped or the other data processing other than the data processing is executed when the elapsed time exceeds the margin time. It is characterized by comprising an executing means for performing.

[0008]

In the real-time data processing apparatus of the present invention, when the processing request is issued from the processing requesting apparatus, the processing content number and the processing request generation time at that time are stored in the storage means. The processing content numbers accumulated in the accumulating means are taken out in the order of accumulation, and the data corresponding to the processing content numbers are processed by the executing means. At that time, the subtraction means calculates the elapsed time from the processing request generation time. This elapsed time is compared with the processing margin time detected by the processing margin time detecting means by the comparing means. When the elapsed time exceeds the processing margin time, the control means stops the execution of the data processing by the execution means. On the other hand, when the elapsed time is within the processing allowance time, the execution of the data processing by the executing means is started.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings. In the present invention, the concept of "processing margin time" is introduced in controlling the data processing in the real-time data processing device. First, this concept will be described. FIG. 3 is an explanatory diagram of the concept of the processing margin time. In this embodiment, it is assumed that the processing time and the time from the processing request generation to the processing completion deadline are determined depending on the processing request content. In this case, a time obtained by subtracting the processing time from the processing request generation time to the processing completion deadline is a margin time from the processing request generation to the processing execution start. This margin time will be used as a reference for data processing control as “processing margin time”.

For example, in FIG. 3, if it becomes possible to execute the process at the process executable time T1 within the process allowance time from the process request generation time T0, the process completion deadline T4 will be in time even if the process time is consumed from that time. .. On the other hand, if it becomes possible to execute the process at the process executable time T2 that has exceeded the process allowance time from the process request generation time T0, the processing completion time T4 cannot be met if the processing time is consumed from that point. More specifically, in FIG. 2, processing A,
For all of B, C, D and E, the time from the generation of a processing request to the completion of processing is set to 1.25 msec. Further, it is known that the processing time is 1.0 msec in each processing. Therefore, the processing margin time in the case of FIG. 2 is 0.25 msec.

In FIG. 2, the process request generation time is t1 and the process A can be executed at the process request generation time t1. Therefore, even if the processing time of 1 msec is consumed from that point, the processing completion deadline t4 can be met. On the other hand, process B
The processing request generation time is t2, but since the processing A is being executed at that time, the processing cannot be executed.
Although the processing margin time of the processing B is 0.25 msec, the processing A
Is executed for 0.75 ms from the processing request generation time t2 of processing B
It will not be completed unless ec has passed. Therefore, it is predicted that the processing B will not be in time for the processing completion deadline t5 even if the processing execution is started after 0.25 msec from the processing request generation time t2. FIG. 4 is a time chart explaining a processing procedure in the apparatus of the present invention. In this figure, the symbols t1, t2, etc. indicating the respective time points on the time axis are
The same reference numerals are used for the time points corresponding to FIG.

In FIG. 4, process A is executed in the same manner as in FIG. 2, but process B is determined not to be processed at time t15 when 0.25 msec has elapsed from the process request generation time t2. As a result, there is no process being executed at the time t3 when the process A is completed. Therefore, the process C can be executed at the process request generation time t4 of the process C. That is, the processing C has a processing margin time of 0.25.
Execution becomes possible within msec and execution starts. And
The processing is completed after the processing time of 1 msec has elapsed. As a result, at the processing request generation time t7 of the processing D, the processing D
Becomes feasible. That is, the processing D has a processing margin time of 0.2.
Execution becomes possible within 5 msec, and execution is started. Then, the processing is completed at time t10 after the processing time of 1 msec has elapsed.

Therefore, the processing request generation time t10 of the processing E
In, the process E becomes executable. That is, the processing E can also be executed within the processing margin time of 0.25 msec, and the execution is started. Then, at time t16 after the processing time of 1 msec has elapsed, the processing is completed. In this way, the processes A, C, D, and E are all completed within the process completion deadline.

FIG. 1 is a block diagram of an embodiment of the real-time data processing apparatus of the present invention. The illustrated apparatus includes a clocking means 1, an accumulating means 2, a subtracting means 3, a processing margin time detecting means 4, a comparing means 5, a controlling means 6, and an executing means 7. The clock means 1 divides the clock signal,
The current time 20 is output at a predetermined time interval. This current time 20 is input to the storage means 2 and the subtraction means 3. The storage unit 2 is composed of a RAM (random access memory), and inputs the processing content number 10 latched in the processing content number input latch 11 and stores it. The processing content number 10 corresponds to the processing A, B, C, D, E and the like. For example, the numbers “1”, “2”, “3”, “4”,
“5” is associated with each process A, B, C, D, E. The executing means 7 extracts the processing content number 10 in the order of accumulation and executes the processing corresponding to the processing content number 10. In this way, the execution of data by the execution means 7 is controlled by the processing content number 10. In addition, such a processing content number 10
Needless to say, the data to be executed may be stored in the storage means 2 as a matter of course.

Further, the accumulating means 2 uses the processing content number 1
The current time 20 at the time of inputting 0 is accumulated corresponding to the processing content number 10. For example, in the example of FIG. 4, the processes A, B,
Times t1, t2, t4, t7, t corresponding to C, D, E
10 is accumulated respectively. Then, the storage means 2 stores the processing content number 10 in the processing margin time detection means 4 and the control means 6.
To the subtraction means 3 when outputting to. The subtraction means 3
When the output means 71 is output from the execution means 7 to the storage means 2, the present time 20 input from the timekeeping means 20 and the request generation time 21 input from the storage means 2 are formed. Calculate the difference between. As a result, the elapsed time 30 after the processing request is generated is obtained.

The processing margin time detecting means 4 is a RAM or an R.
Process A consists of OM (Read Only Memory)
The processing margin time of FIG. 3 is stored corresponding to B, C, D, and E. In the example of FIG. 4, the processing allowance time is 1 ms in each case.
ec. The comparison means 5 comprises an arithmetic circuit such as a comparison circuit or a subtraction circuit, and the elapsed time 3 input from the subtraction means 3
0 is compared with the processing margin time 40 input from the processing margin time detection means 4. As a result, it is determined whether the elapsed time 30 exceeds the processing margin time 40. The comparison result 50 is output to the control means 6. Control means 6
Executes the processing content number 10 input from the storage means 2 in accordance with the comparison result 50 input from the comparison means 5.
Or the output instruction 71 to the storage means 2 is output. That is, the control means 6 outputs the output instruction 71 of the next processing content number to the storage means 2 when the elapsed time from the generation of the processing request exceeds the processing margin time. As a result, the processing content number 10 output from the accumulating means 2 is ignored, and the subtracting means 3, the processing margin time detecting means 4 and the comparing means 5 start execution control for the next processing. on the other hand,
When the elapsed time from the generation of the processing request is within the processing margin time, the processing content number output from the accumulating means 2 is directly output to the executing means 7.

The execution means 7 receives the data corresponding to the processing content number 10 input from the control means 6 and sends the data to the processing request device 8.
To be executed via the bus 9. The data in this case is always in time for the processing completion deadline by the execution of the execution means 7. Not limited to this, when the elapsed time from the generation of the processing request exceeds the processing margin time, the control means 6 sends the fact and the processing content number to the execution means 7, and the execution means 7 determines the execution time. There is no problem even if another short process is executed. Next, the operation of the above-mentioned device will be described. FIG. 5 is a time chart explaining the operation of the apparatus of FIG. When the data to be processed occurs, the processing requesting device 8 outputs the processing content number 10 corresponding to the data. The processing content number 10 is latched in the processing content number input latch.

When the input instruction 70 output at a predetermined time interval is input from the execution means 7, the processing content number 10 in the processing content number input latch 11 is stored in the storage means 2.
Then, the current time at this time, that is, the processing request generation time is accumulated. As a result, the process content numbers of the process A are accumulated, and the process request occurrence times t1 corresponding to these are accumulated.

When the output instruction 71 is input from the execution means 7, the processing content number 10 of the processing A and the processing request generation time t1 are output from the storage means 2. The subtraction means 3 subtracts the processing request generation time t1 from the current time. As for the process A, the execution means 7 can be executed at the same time when the process request is generated, and therefore the output instruction 71 is output at the process request generation time t1. Further, the comparison means 5 compares the result of the subtraction means 3 with
The processing margin time of the processing A is compared. Here, the operation timing of the comparison means 5 is as shown in FIG.
And the processing margin time detection means 4 is set at the time of determination. In this case, since the elapsed time as a result of the subtraction means 3 is almost 0 msec, the control means 6 sends the processing content number of the processing A to the execution means 7. As a result, the executing means 7
The data of the process A is taken out from the process requesting device 8 via the bus 9 and executed. As a result, the process A is executed within the predetermined time. A processing request for processing B occurs while the execution means 7 is executing processing A. The processing content number of the processing B and the processing request generation time t2 are stored in the storage means 2 as in the case of the processing A. When the execution means 7 completes the execution of the process A, the execution means 7 outputs the next output instruction 71.

When the next output instruction 71 is input from the execution means 7, the processing content number 10 of the processing B and the processing request generation time t2 are output from the storage means 2. The subtraction unit 3 subtracts the processing request generation time t2 from the current time. As for the process B, the execution means 7 can be executed at the completion of the execution of the process A. Therefore, the output instruction 71 is output after a considerable time has elapsed from the process request generation time t2. Also, the comparison means 5
Compares the result of the subtraction means 3 with the processing margin time of the processing A. In this case, the elapsed time resulting from the subtraction means 3 is approximately 1 msec, which exceeds the processing margin time of 0.25 msec. Therefore, the control means 6 sends the next output instruction 71 to the execution means 7. As a result, the execution unit 7 ignores the process B.

When the next output instruction 71 is input, since the storage means 2 is empty, nothing is output. Then, after about 0.25 msec has elapsed, a processing request for processing C is generated. The processing content number of this processing C and the processing request occurrence time t4 are
It is stored in the storage means 2 as in the case of the processes A and B. At this time, since the execution means 7 is executable, it outputs the output signal 71 at every predetermined time. By inputting this output signal 71, the processing content number 10 of the processing C from the storage means 2 is input.
And the processing request occurrence time t4 are output. Subtraction means 3
Subtracts the processing request generation time t4 from the current time. Since the execution means 7 can execute the process C before the process request is generated, the output instruction 71 is output at the process request generation time t4. Further, the comparison means 5 compares the result of the subtraction means 3 with the processing margin time of the processing C.
In this case, the elapsed time resulting from the subtraction means 3 is almost 0.
Since it is msec, the control means 6 sends the processing content number of the processing C to the execution means 7. As a result, the execution means 7 extracts the data of the process C from the process requesting device 8 via the bus 9 and executes it. As a result, the process C is executed within the predetermined time. When the execution means 7 almost completes the execution of the process C,
A processing request for processing D occurs. The processing content number of the processing D and the processing request occurrence time t7 are accumulated in the accumulating unit 2 as in the case of the processing A, B, and C. When the execution means 7 completes the execution of the process C, it outputs the next output instruction 71.

When the next output instruction 71 is input, the processing content number 10 of the processing D and the processing request generation time t7 are output from the storage means 2. The subtraction means 3 subtracts the processing request generation time t7 from the current time. As for the process D, the execution means 7 can execute the process request at substantially the same time as the process request is generated, and therefore the output instruction 71 is output at the process request generation time t7. Further, the comparison means 5 compares the result of the subtraction means 3 with the processing margin time of the processing D. In this case, since the elapsed time as a result of the subtraction means 3 is almost 0 msec, the control means 6 determines the processing content number of the processing D by the execution means 7.
Send to. As a result, the execution means 7 extracts the data of the process D from the process requesting device 8 via the bus 9 and executes it. As a result, the process D is executed within the predetermined time. When the execution means 7 almost completes the execution of the processing D, a processing request for the processing E is generated. The processing content number of the processing E and the processing request generation time t10 are stored in the storage unit 2 as in the case of the processing A, B, C, and D. When the execution means 7 completes the execution of the process D, the execution means 7 outputs the next output instruction 71. With the next output signal 71, processing E is performed in exactly the same manner as processing D.
Is executed.

FIG. 6 is a flowchart for explaining the processing procedure of the control program when the real-time data processing device of the present invention is realized by a digital processor. A timer means 1, an accumulating means 2, and a processing margin time detecting means 4 shown in FIG. 1 are prepared together with a digital processor for executing the control program shown in the figure. On the other hand, the functions of the subtraction unit 3, the comparison unit 5, and the control unit 6 of FIG. 1 are realized by the program of FIG. The program of FIG. 6 is executed at a predetermined time interval by a timer interrupt by a signal generated by the time measuring means 1 at a predetermined cycle. First, it is determined whether or not there is a processing request from the processing request device (step S1). When there is a processing request, the processing or processing content number and the processing request generation time are stored in the storage means (step S2).

Next, it is determined whether or not the processing means can be executed (step S3). If it is not executable, only processing requests are accumulated (steps S1 and S2). If the processing means can be executed, the elapsed time from the request generation is calculated (step S4). Then, it is determined whether or not the elapsed time exceeds the processing margin time (step S5). When the elapsed time exceeds the processing margin time, the execution of the processing extracted from the accumulating unit is stopped (step S6). When the elapsed time is within the processing allowance time, the execution of the processing extracted from the storage means is started (step S7).

[0025]

As described above, according to the real-time data processing apparatus of the present invention, the concept of processing margin time is introduced,
When the elapsed time from the generation of the processing request exceeds the processing margin time, the data processing is stopped or another processing is performed, so that it is possible to avoid executing the processing that is not in time for the processing completion deadline. It is possible to omit the execution of various processes. As a result, the execution start time of the data of the next processing request can be advanced, and the processing completion deadline can be made in time. Therefore, it is possible to improve the processing capacity for data that is effectively processed.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a real-time data processing device of the present invention.

FIG. 2 is a time chart illustrating a processing procedure in a conventional device.

FIG. 3 is an explanatory diagram of a concept of processing margin time.

FIG. 4 is a time chart explaining a processing procedure in the apparatus of the present invention.

5 is a time chart explaining the operation of the apparatus of FIG. 1. FIG.

FIG. 6 is a flowchart illustrating a processing procedure of a control program when the real-time data processing device of the present invention is realized by a digital processor.

[Explanation of symbols]

 1 Timekeeping Means 2 Accumulating Means 3 Subtracting Means 4 Processing Allowance Time Detecting Means 5 Comparing Means 6 Control Means 7 Executing Means 8 Processing Requesting Devices

Claims (1)

[Claims] 1. A clocking means for outputting a current time, a storage means for storing a requested process and a request generation time output from the clocking means at the time of request, and a storage means based on a current time output by the clocking means. Subtraction means for obtaining the elapsed time from the request time by subtracting the request generation time accumulated in, a processing margin time detecting means for detecting a margin time until the start of the processing accumulated in the accumulating means, The comparison means for comparing the elapsed time output by the subtraction means with the allowance time detected by the processing allowance time detecting means, and the result of the comparison by the comparing means, depending on whether or not the elapsed time exceeds the allowance time, Controlling means for controlling the processing accumulated in the accumulating means, and executing predetermined data processing when the elapsed time is within the margin time according to the control of the controlling means, When the elapsed time exceeds the margin time, the predetermined data processing is stopped, or an execution unit for executing other data processing other than the data processing is provided. Time data processing device.