CN-121764422-B - Task control system for high-speed printing

CN121764422BCN 121764422 BCN121764422 BCN 121764422BCN-121764422-B

Abstract

The invention relates to the technical field of task control and discloses a task control system for high-speed printing, which comprises a state monitoring unit, a parameter adjusting unit and a cooperative control unit, wherein the state monitoring unit is used for collecting task queue load capacity and task completion time estimated values and calculating back pressure hysteresis state indexes based on mapping distribution of the task queue load capacity and the task completion time estimated values in a history window, the parameter adjusting unit is used for converting the back pressure hysteresis state indexes into system compensation gain coefficients, and the cooperative control unit is used for synchronously adjusting scoring weights, rasterization processing parallelism and cache resource quota of task scheduling sequencing in response to the system compensation gain coefficients and generating updated task completion time estimated values by combining real-time transmission rates of data channels and data stream supply continuity indexes. The invention can quantify and compensate the backpressure hysteresis effect of the system under the concurrent of multiple tasks, and improve the precision of the operation completion time estimation and the adaptability of the scheduling strategy while guaranteeing the stable supply of data streams.

Inventors

YUAN XUGUANG
CAO YONG
CHEN ZAIMIN

Assignees

上海融跃电子科技股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260302

Claims (6)

1. A job control system for high-speed printing, comprising: The state monitoring unit is used for collecting load data of a job queue and task completion time predicted values output by a system, calculating back pressure hysteresis state indexes based on mapping distribution conditions of the load data and the task completion time predicted values in a history window, and comprises the following steps: The state monitoring unit maintains a first-in first-out queue with preset length as a history window, wherein the history window stores the data pairs of the load data and the task completion time predicted value of a plurality of latest control periods, and writes the latest data pairs into the history window and removes the earliest data pairs in the current control period; The state monitoring unit divides the value range of the load data into a plurality of load barrel dividing intervals according to a preset maximum load capacity threshold value and a preset maximum time threshold value, divides the value range of the task completion time predicted value into a plurality of time grading intervals, and counts the frequency of data pairs in the history window falling into two-dimensional grids formed by the load barrel dividing intervals and the time grading intervals; the state monitoring unit calculates conditional probability distribution of distribution frequency of the data falling into each load barrel division interval on the basis of the distribution frequency of the data on each time barrel division interval, and calculates a conditional entropy value corresponding to the load barrel division interval according to a shannon entropy formula; The state monitoring unit counts the occurrence frequency of each load barrel division interval in the history window as a weighting coefficient, and performs weighted summation on the conditional entropy values corresponding to all the load barrel division intervals to obtain the back pressure hysteresis state index; the parameter adjusting unit is used for establishing a mapping relation between the back pressure hysteresis state index and a system compensation gain coefficient and generating the system compensation gain coefficient of the current control period; The collaborative control unit is used for responding to the system compensation gain coefficient, synchronously adjusting the grading weight, the rasterization processing parallelism degree and the cache resource quota of the task scheduling sequence, and also used for collecting the real-time transmission rate of the data channel and the data stream supply continuity index and generating the updated task completion time predicted value by combining the system compensation gain coefficient.
2. The job control system for high-speed printing according to claim 1, wherein collecting the load data of the job queue and the job completion time predicted value outputted by the system comprises: the state monitoring unit acquires the original data size, the priority parameter and the submitting time stamp of each job task to be processed in real time through a network interface; the state monitoring unit divides the original data size by a preset reference data size unit to obtain an equivalent data size, normalizes the priority parameter into a relative priority value in a preset value interval, converts the submitting timestamp into a relative time value relative to the starting moment of the current control period, and further combines the equivalent data size, the relative priority value and the relative time value into a normalized feature vector of each task to be processed; The state monitoring unit traverses all outstanding job tasks to be processed in a current job queue set, and accumulates the equivalent data quantity of all the job tasks to be processed to obtain load data of the job queue; and simultaneously, the state monitoring unit reads the task completion time predicted value which is output by the cooperative control unit in the last control period and is stored in the system memory.
3. The job control system for high-speed printing according to claim 2, wherein the parameter adjustment unit establishes a mapping relationship between the back pressure hysteresis state index and a system compensation gain coefficient, the mapping relationship is configured such that when the back pressure hysteresis state index increases, the system compensation gain coefficient monotonically decreases, and a value range of the system compensation gain coefficient is limited within an open interval between zero and one.
4. A high-speed printing task control system according to claim 3, wherein establishing a mapping relationship between the back pressure hysteresis state index and a system compensation gain coefficient, generating the system compensation gain coefficient of a current control cycle, comprises: the parameter adjusting unit is pre-provided with a first calibration parameter and a second calibration parameter and is used for constructing a reverse linear transformation relation; the parameter adjusting unit calculates the product of the first calibration parameter minus the second calibration parameter and the back pressure hysteresis state index to obtain a linear intermediate variable; And the parameter adjusting unit substitutes the linear intermediate variable serving as an input independent variable into an S-shaped function to perform nonlinear operation, so that the system compensation gain coefficient is obtained.
5. The system of claim 4, wherein responsive to the system compensation gain factor, synchronously adjusting the scoring weight of the task scheduling ordering, the rasterization processing parallelism, and the cache resource quota comprises: the cooperative control unit obtains predicted service time based on the normalized feature vector of each job task to be processed, calculates basic scheduling scores according to the predicted service time, and calculates conservative scheduling scores according to equivalent data quantity, relative priority value and relative time value in the normalized feature vector of each job task to be processed; The cooperative control unit takes the system compensation gain coefficient as the weight of the basic scheduling score, takes a difference value obtained by subtracting the system compensation gain coefficient as the weight of the conservative scheduling score, respectively carries out weighted summation based on the weight of the basic scheduling score and the weight of the conservative scheduling score to obtain a mixed scheduling score, and converts the mixed scheduling score into the execution probability of each job task to be processed based on an exponential normalization function so as to adjust the scoring weight of the task scheduling sequence; The cooperative control unit performs linear interpolation calculation by utilizing the system compensation gain coefficient based on a preset minimum parallel stroke number and a preset maximum parallel stroke number, and rounds up the calculation result, so that the rasterization processing parallelism of the current control period is determined; And the cooperative control unit performs inverse linear interpolation calculation by utilizing a difference value obtained by subtracting the system compensation gain coefficient based on the preset minimum buffer block number and the preset maximum buffer block number, and rounds down the calculation result, thereby obtaining the buffer resource quota of the current control period.
6. The high-speed printing job control system according to claim 5, wherein collecting real-time transmission rate of data channels and data stream supply continuity index, and generating the updated job completion time estimate in combination with the system compensation gain factor, comprises: the cooperative control unit counts the total data amount successfully output to the printing engine in the current control period, converts the total data amount into equivalent data amount, and divides the equivalent data amount by the control period duration to obtain the real-time transmission rate; The cooperative control unit records a time interval sequence between two adjacent data output blocks in a sliding window, calculates the ratio of the standard deviation to the average value of the time interval sequence, and obtains the data stream supply continuity index; The cooperative control unit calculates a continuity penalty term based on a natural exponential function by using a preset continuity penalty coefficient and the data stream supply continuity index, and calculates a hysteresis reduction term by using a preset minimum service rate reduction proportion and the system compensation gain coefficient; and the cooperative control unit divides the load capacity data of the job queue by the hysteresis correction service rate to obtain the updated task completion time estimated value.

Description

Task control system for high-speed printing Technical Field The invention relates to the technical field of task control, in particular to a task control system for high-speed printing. Background In a production digital printing system, a Digital Front End (DFE) is responsible for interpreting and rasterizing a received job file into a bitmap data stream that can be parsed by a print engine, and then continuously supplying the print engine for imaging output. To maximize production efficiency, modern DFEs typically employ multi-core parallel processing architecture to address the challenges of high resolution and high variable data volumes, and to provide a buffer mechanism between the rasterization module and the print engine to smooth fluctuations in the data flow. However, in actual high-speed print jobs, there are often beat constraints for the print engine. Once the upstream data feed rate is lower than the engine consumption rate, resulting in buffer underruns, the print engine often needs to enter a down, idle, or re-warm state, which can result in significant capacity loss and recovery overhead. Existing task control and scheduling techniques typically estimate completion time and formulate scheduling strategies based solely on task size, priority, or commit time in the job queue. The static or instantaneous assessment method based on the current snapshot can still operate in a single-task or low-load environment, but often fails in a multi-task high-concurrency scene. This is because the concurrency of multiple tasks can cause nonlinear contention for memory bandwidth and cache resources, resulting in bursty fluctuations in the rasterization yield. More importantly, the prior art ignores path dependency or hysteresis within the system, i.e., the same amount of job load, which requires a substantially different actual processing time when the system is in a steady supply state versus a recovery after interruption state. Because the prior art cannot effectively quantify the complex historical memory effect caused by back pressure propagation and engine state switching, huge deviation of the completion time estimated value is often caused. The deviation can further mislead the scheduler, so that the scheduler cannot take conservative inhibition measures at the critical point of the data flow about to be interrupted, but can increase concurrency rapidly, aggravate resource contention, and finally cause the system to be frequently involved in the oscillation cycle of supply interruption and recovery, thereby seriously affecting the overall throughput rate and system stability. Disclosure of Invention The invention provides a task control system for high-speed printing, which solves the technical problems in the background technology. The invention provides a task control system for high-speed printing, which comprises the following components: The state monitoring unit is used for collecting load data of the job queue and task completion time predicted values output by the system, and calculating back pressure hysteresis state indexes based on mapping distribution conditions of the load data and the task completion time predicted values in a history window; the parameter adjusting unit is used for establishing a mapping relation between the back pressure hysteresis state index and a system compensation gain coefficient and generating the system compensation gain coefficient of the current control period; The collaborative control unit is used for responding to the system compensation gain coefficient, synchronously adjusting the grading weight, the rasterization processing parallelism degree and the cache resource quota of the task scheduling sequence, and also used for collecting the real-time transmission rate of the data channel and the data stream supply continuity index and generating the updated task completion time predicted value by combining the system compensation gain coefficient. The method has the advantages that the back pressure delay state caused by resource contention and supply cutoff in a multi-task concurrency scene is effectively identified by establishing the mapping distribution relation between the work load and the time estimated value in a history window, the surge degree of a scheduling strategy, the concurrency scale of rasterization processing and the resident quota of cache resources are synchronously adjusted by utilizing a continuous system compensation gain coefficient, when the system is in a high delay state, task burst is automatically restrained, the buffer absorption capacity is increased, thereby avoiding productivity reduction of a downstream engine caused by supply interruption, and meanwhile, the service rate is corrected by introducing a data stream supply continuity index, the multi-value and path dependence of a single-dimension estimated value are eliminated, and the accuracy of the estimation of the completion time of a high-speed printing job and the stab