JP2006252298A - Printing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printing system capable of preferentially printing a high priority job. <P>SOLUTION: The printing system with a host computer and an image forming apparatus connected through a network comprises a job scheduler function, a task manager, and a broker function for all systems to be clients. The task manager receives a print job, acquires priority information from the received job, and requests the job scheduler through the broker to analyze a resource status. The job is distributed to the broker according to the resource status. The broker receives the job from the task manager, acquires the priority information from the received job, changes a CPU utilization ratio based on the priority information, and performs the job. When the job is completed, the task manager is notified of the completion. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a printing system in which a grid computing load distribution system is applied to a printer or a multi-function printing apparatus connected to a host computer via an interface.

  FIG. 1 is a diagram for explaining the architecture of grid computing applied to the present invention.

  Although there are several types of grids, what is described here is a type called a desktop grid, which executes a job by using the free time of a CPU such as a desktop PC.

  The client in FIG. 1 is a user who submits a job, and the request (job) is transferred to a task manager (hereinafter abbreviated as TM) and the contents are transmitted to a dynamic job scheduler (hereinafter abbreviated as DJS). .

  The DJS performs overall resource management, selects an optimal resource broker, and notifies the TM (this resource refers to a free CPU state here).

  The Broker registers the information of the resource that has been picked up by the resource manager (hereinafter abbreviated as RM) in the DJS, submits a job to the optimal resource in response to a request from the TM, and notifies the TM of completion.

  The TM submits the job to the optimal Broker selected by the DJS, and thereafter monitors the progress of the job. When the TM receives a completion notification from the Broker, the TM notifies the user of the result. Also, if there is a change / abnormality in the resource (eg, failure, other job accepted), the RM notifies the Broker.

  The realization of desktop grid computing is that distributed processing is possible by allocating jobs to resources such as CPUs (which are not normally used) that are optimal in such a mechanism.

  Next, the configuration when this technology is applied to the PDL processing of the image forming apparatus will be described with reference to FIG. In the description of FIG. 1, each module constituting the grid is treated as a separate one. However, when applied to a printing apparatus, a plurality of modules generally exist in one device.

  In FIG. 2, a client PC that issues a print instruction (job input) inputs a print job, has an TM and DJS function in the image forming apparatus, and has Broker, RM in PC1, PC2, and PC3, for example, using three PCs. A device configuration to which distributed processing by grid computing is applied.

  A job (PDL print job data) input from a client is divided into resources of PCs 1, 2, and 3 via TM and DJS of the image forming apparatus. At this time, an application program for PDL data image expansion processing is also transmitted from the image forming apparatus at the same time.

  An image that has been distributed and executed for PDL image formation on each PC is collected by an image forming apparatus and finally output using a grid mechanism.

This distributed processing target resource may be three or more PCs, and even if it includes the resource of the client PC of the job submission source, the resources of the image forming apparatus on the same network are used as targets. Also good.
IBM professional paper "Applicability of grid computing to commercial systems"<http: // www-6. ibm. com / jp / provision / no36 / pdf / 36_ppr1. pdf>

  In recent years, research on gathering CPU power of computers using grid computing technology to realize high-speed processing has been active in science-related research, but application to embedded devices is still unparalleled.

  When the grid technology is utilized in the printing system, a plurality of print jobs may be allocated to one CPU. However, since Grid has no concept of priority, all print jobs are allocated evenly according to resource availability, and other print jobs can be output for high-priority print jobs. There is a risk of having to.

  The present invention has been made paying attention to the above-mentioned problems, and provides a printing system capable of preferentially printing a job having a high priority by simultaneously notifying the priority of the job when distributing the job. The purpose is to do.

  In order to solve the above-described problems, a system according to the present invention is connected to a host computer and an image forming apparatus via a network, and has a job scheduler function and a broker function in all systems serving as a task manager and a client. In the printing system, the task manager includes a means for receiving a print job, a means for obtaining priority information from the received job, and a means for requesting the job scheduler to analyze a resource status via the broker. The job scheduler has means for analyzing the resources, and means for notifying the task manager of the analysis result, A broker, means for receiving a job from the task manager; Means for reading priority information from the received job, means for changing the CPU utilization based on the read priority information, means for executing the job, and exiting to the task manager when the job is finished Means for performing notification.

  When a grid computing technique is applied to an image forming apparatus, printing can be efficiently performed according to the priority of a print job.

  Hereinafter, the present invention will be described in detail with reference to the drawings based on the effective embodiments thereof.

[First embodiment]
(Hard structure of image forming apparatus)
FIG. 3 is a diagram illustrating an appearance of an image forming apparatus having a copying function. A scanner 201 that is an image input device illuminates an image on paper as a document, and scans a CCD line sensor (not shown) to generate raster image data.

  When the user sets the original paper on the tray 203 of the original feeder 204 and instructs the start of reading in the operation unit 202, the controller CPU of the image forming apparatus gives an instruction to the scanner 201, and the feeder 203 sets the original paper 1 Each sheet is fed, and the scanner 201 performs an original image reading operation.

  An operation unit 202 is a user interface for specifying setting instructions, status display, and various operation settings during a copy operation.

  The printer engine 103, which is an image output device, is a part that prints raster image data on paper. The method includes an electrophotographic method using a photosensitive drum or a photosensitive belt, an ink jet method in which ink is ejected from a micro nozzle array and an image is directly printed on a sheet, and any method may be used. The printing operation is activated by an instruction from the controller CPU.

  The printer engine 103 has a plurality of paper feed stages so that different paper sizes or different paper orientations can be selected, and there are paper cassettes 206, 207, 208 corresponding thereto. The paper discharge tray 205 receives paper that has been printed.

  FIG. 4 is a block diagram illustrating a control configuration of the image forming apparatus. The printer controller 102 is connected to the scanner 201 as an image input device and the printer engine 103 as an image output device. On the other hand, the printer controller 102 inputs and outputs print data, image information, and device information to and from the host via the host I / F 308. do.

  The CPU 301 is a controller that controls the entire system. A RAM 302 is a system work memory used for the CPU 301 to operate. The RAM 302 is also an image memory for temporarily storing image data. A ROM 303 is a boot ROM, and stores a system boot program. An HDD 304 is a hard disk drive and stores system software and image data.

  The operation unit I / F 306 controls an interface with the operation unit (UI) 202 and outputs image data to be displayed on the operation unit 202 to the operation unit 202. Further, it plays a role of transmitting information input by the user via the operation unit 202 to the CPU 301. Further, environment setting information such as an operation mode input from the operation unit 202 is stored in the NVRAM 316 which is a nonvolatile memory.

  The host interface 308 inputs / outputs information to / from the host 001. The above devices are arranged on the system bus 307.

  An image bus interface (Image Bus I / F) 305 is a bus bridge that connects a system bus 307 and an image bus 309 that transfers image data at high speed, and converts a data structure. The following devices are arranged on the image bus 309. A raster image processor (RIP) 310 expands a PDL code transmitted from a network into a bitmap image. A device I / F unit 311 connects the scanner 201 and the printer engine 103, which are image input / output devices, and the printer controller 102, and performs synchronous / asynchronous conversion of image data.

  The scanner image processing unit 312 corrects, processes, and edits input image data. A printer image processing unit 313 performs printer correction, resolution conversion, and the like on print output image data. The image rotation unit 314 rotates image data. The image compression unit 315 performs JPEG compression / new tone processing for multi-valued image data, and performs compression / decompression processing such as JBIG, MMR, and MH for binary image data.

(Software configuration of image forming apparatus)
FIG. 5 is a flowchart for explaining the use of the Grid according to the priority of the print job in the image forming apparatus of the first embodiment. The background grid computing technology and configuration are the same as those described in FIGS.

  Here, the processing in the image forming apparatus of the flow of FIG. 5 is executed under the control of the CPU 301 in accordance with the system program stored in the HDD 304 of FIG.

  Hereinafter, the flow of using the Grid according to the priority of the print job in the image forming apparatus will be described first with reference to the flowchart of FIG.

  In the drawings, the step is denoted as S.

  In step 501, TM continues to wait for a print job received from the client PC used by the user. When the print job is released from waiting for reception, the process advances to step 502 to perform job reception processing. In step 503, priority information is acquired from the received job. Here, the priority information is information used to determine the priority of a job, and refers to, for example, a time limit time for completion of printing. Next, in step 504, a resource status analysis request is made to the DJS in preparation for distributed job submission. The DJS receives the analysis request and performs resource analysis via the Broker in step 507. In step 508, the analysis result is notified to TM. In TM, in response to the analysis result of the resource status, the job is distributed and submitted in step 505. When performing this distributed input, the priority of the job acquired in step 503 is also notified to the broker at the same time.

  In the broker, the job is released from waiting for reception in step 509 when the job is input. Then, the process proceeds to step 510, and the priority of the input job is acquired. In step 511, the obtained priority information is compared with other jobs currently being executed, and the CPU utilization rate is changed based on the result.

  Next, in step 512, the job is executed. In step 513, the end of the job is notified to the TM.

  By performing such control, for example, if the submitted job has a time limit time approaching more than others, the priority is the highest and the CPU usage rate is changed to the highest. be able to. As a result, the job can be completed as close as possible to the priority order.

  Although the control program for the grid described above is applied to the image forming apparatus here, the elements constituting the grid may be provided independently to the server or another PC.

[Second Example]
In the first embodiment, priority information such as a time limit designated by the client PC is notified to each Broker, so that the CPU usage rate can be changed according to the priority when a job is submitted in the Broker. The CPU utilization rate may be changed dynamically not only when a job is submitted but also according to the job status.

  In FIG. 6, priority information is not used when a job is submitted, and the CPU usage rate is evenly allocated to a plurality of jobs. However, the overall progress of the job exceeds 70%, and some distributed jobs become a bottleneck. This is a processing flow for controlling the CPU usage rate to increase in the CPU that is the bottleneck in such a situation.

  In step 601, the TM confirms the status of jobs that are sequentially submitted to the DJS. In step 604, the DJS waits for an inquiry from the TM. If there is an inquiry, the process proceeds to step 605 to check the progress of the job. In step 606, the analysis result is notified to the TM. The TM determines whether the progress of the job exceeds 70% from the notification received in step 602. If it does not exceed, return to step 601 and repeat the status check. If it exceeds 70%, in step 603, an instruction for increasing the CPU usage rate is notified to the broker of the CPU that is the bottleneck. The Broker waits for an instruction from the TM in step 607. If the instruction is received, the process proceeds to step 608, where an instruction to increase the CPU utilization rate is read. In step 609, the CPU usage rate for the job designated is increased. In step 610, the job is executed again. When the job execution is completed, an end notification is sent from step 611 to TM.

  By adopting such a configuration, even when a bottleneck occurs, it can be easily resolved.

[Other Examples]
The program code and related data according to the present invention can be stored in a floppy (registered trademark) disk (FD) or a CD-ROM and supplied to the computer from there. In addition, an object of the present invention is to supply a storage medium storing a program code of software (control program) for realizing the functions of the above-described embodiments to a computer as shown in FIG. Is achieved by reading and executing the program code stored in the storage medium. As a method of supplying a program and data to a computer, a method of storing the program and data in a floppy (registered trademark) disk FD700 and supplying it to a computer main body 702 (via a floppy (registered trademark) disk drive 701) as shown in FIG. Is. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.

  As a storage medium for supplying the program code, for example, in addition to a floppy (registered trademark) disk and a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM Etc. can be used. Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) operating on the computer based on the instruction of the program code. It goes without saying that a case where the function of the above-described embodiment is realized by performing part or all of the actual processing and the processing is included. Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

It is a figure which shows the structure of the grid computing of background art. It is a figure which shows the structure at the time of applying to the PDL process of background art. 1 is a diagram illustrating an overview of an image forming apparatus. 2 is a block diagram illustrating a control configuration of the image forming apparatus. FIG. It is a flowchart which shows the process of a 1st Example. It is a flowchart which shows the process of a 2nd Example. It is a figure which shows the supply method of a program code.

Explanation of symbols

001 Host computer 101 Entire image forming apparatus 102 Entire printer controller 103 Printer engine

Claims (2)

In a printing system in which a host computer and an image forming apparatus are connected via a network and a job scheduler function and a broker function in all systems that are a task manager and a client,
The task manager includes means for receiving a print job, means for obtaining priority information from the received job, means for requesting the job scheduler to analyze a resource status via the broker, and a resource status. And a means for distributing and submitting jobs to the broker in response.
The job scheduler has means for analyzing resources, and means for notifying a task manager of an analysis result,
The broker executes a job, a means for receiving a job from the task manager, a means for reading priority information from the received job, a means for changing a CPU usage rate based on the read priority information, and a job And a means for notifying the task manager when the job is completed. In the task manager, means for confirming the progress of the job to the job scheduler, means for determining whether the progress exceeds a specified value, and the processing is not completed when the specified value exceeds the specified value Means for instructing the broker to increase the CPU utilization rate,
The job scheduler has means for analyzing the progress of the job in response to an instruction from the task manager, and means for notifying the task manager of the analysis result,
The broker has means for reading an instruction from the task manager, means for increasing the CPU usage rate in response to the instruction, means for executing a job, and notification of completion to the task manager when the job is completed. And a printing system.

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