JPH04188332A - Data outputting system - Google Patents

Abstract

PURPOSE:To allocate a CPU uniformly to the processes of a CPU boundary and an I/O boundary by referring to an access inhibition information table, and issuing an output instruction after storing data in an area in an output data area other than an access inhibited area. CONSTITUTION:By issuing the output instruction by the process to which the CPU is allocated, this process is registered in a timer queue 3, and simultaneously, information showing the area in the data output area in which the process stored output data to an output device is stored in the access inhibition information table 8 as the information to show the access inhibited area. Then, by completing the output of the data to the output device by a data output means, the process registered in the timer queue 3 is re-registered in the queue 3, and simultaneously, the information related to this process in the access inhibition information table 8 is deleted, and the area in the output data area having been used by the process for outputting the data is released. Thus, the CPU can be allocated uniformly to the processes of the CPU boundary and the I/O boundary.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention uses a process as a unit of CPU allocation, registers a plurality of processes in a queue, and assigns a CPU according to their respective priorities.
The present invention relates to a data output method for outputting data from a computer system that determines the order of PU allocation to an output device.

[Prior Art] Processes, which are the unit of CPU allocation in a computer system, are generally registered in a queue, and those with higher priority receive CPU allocation. By the way, the CPU
When a process that has been allocated an output command issues an output command to an output device such as a printer, conventionally, the data output area on the buffer where the output data to the output device is stored is immediately released after the data output is completed, and the resources are made available. In order to utilize the output command, the priority of the process that issued the output command is increased. By doing this, the CPU is immediately assigned to the process that issued the output command after the data output processing is completed, and the area in the data output area that was used for data output is released by this process, making effective use of resources. can be achieved. Note that a process whose priority level has been increased due to data output is returned to its original priority level by being assigned a CPU again after data output is completed.

[Problem to be solved by the invention]

As mentioned above, conventionally, when a process to which a CPU is assigned issues an output command, the priority of that process is increased, so a CPU that rarely outputs data
If a U boundary process and an I10 boundary process that frequently outputs data are registered in the queue, there is a problem that the CPU cannot be allocated to the CPU boundary process.

An object of the present invention is to be able to release the output data area immediately after data output is completed, and to be able to release the output data area immediately after data output is completed, and to
The object of the present invention is to provide a data output method that allows CPUs to be allocated on average to 10 boundary processes.

[Means to solve the problem]

In order to achieve the above object, the present invention has a queue in which a plurality of processes are registered, and based on the priority of each process registered in the queue, CPU
In a data output method in which data is output from a computer system to an output device, the computer system includes: an output data area in which data output by a process to the output device is stored; and an output data area in the output data area. An access prohibition information table in which information indicating an access prohibited area of the CPU is registered, and a process assigned to the CPU issues an output command, thereby sending a read command request to the output device and controlling the access of the CPU. read command requesting means for registering information indicating an area in the data output area in which the allocated process has stored data in the access prohibited information table as information indicating an access prohibited area; and a process to which the CPU has been allocated. registers the process in the timer queue by issuing an output command, re-registers the process registered in the timer queue in the queue by receiving a read completion notification from the output device, and also registers the process in the access prohibition information table. read completion waiting means for deleting information related to the process from the output device; and data output means for reading data stored in the output data area and outputting it to the output device when a read command is added from the output device. The output device includes: read command issuing means for issuing a read command to the data output means in response to the read command request; and a read command issuing means for issuing a read command to the data output means in response to the read command request; and completion notification means, the process refers to the access prohibition information table when outputting data to the output device, stores the data in an area other than the access prohibited area in the output data v4 area, and then outputs the data. Issue orders.

In addition to the above configuration, the present invention also provides the above configuration in order to enable the output data area to be released even if data output is not completed even after a predetermined period of time has passed after a process issues an output command. If a read completion notification is not output from the output device even after a predetermined period of time has passed after registering a process in the timer queue in the computer system, the process registered in the timer queue is aborted and the access is prohibited. A process abort means is provided for deleting information regarding the process from the information table.

[For production]

When a process to which a CPU is assigned outputs data to an output device, it refers to the access prohibition information table, stores the data in an area other than the access prohibited area, and then
Issue an output command.

When a process allocated to the CPU issues an output command, the read command request means outputs a read command request requesting the output device to issue a read command, and also outputs an area in the output data area in which the process stores data. The information indicating the access-prohibited area is registered in the access-prohibited information table as information indicating the access-prohibited area. Further, the read completion waiting means registers the process to which the CPU has been assigned in the timer queue by issuing a data output command.

When the read command issuing means provided in the output device receives the read command request output by the read command requesting means, it outputs a read command.

When the data output means in the computer system receives a read command from the output device, it reads the data stored in the output data area and outputs it to the output device. Then, when the data output is completed, the read completion notification means in the output device outputs a read completion notification.

When the waiting means in the computer system receives the read completion notification from the output device, it re-registers the process registered in the timer queue in the queue and deletes information regarding the process from the access prohibition information table.

Further, the process abort means in the computer system aborts the process registered in the timer queue if a read completion notification is not output from the output device even after a predetermined period of time has passed after registering the process in the timer queue, and Delete information about that process from the access prohibition information table.

〔Example〕

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, which is composed of a host computer 1 and a printer device 12. As shown in FIG.

The host computer 1 stores a queue 2 in which a plurality of processes are registered, a timer queue 3 in which processes waiting for output completion are registered, a process 4 in progress to which a CPU is assigned, and output data to a printer device 12. An output data area 5 provided on the sofa, an output processing occurrence detection means 6 for detecting that the process 4 in process has issued an output command, and an output processing occurrence detection means for detecting the issuance of a forceful command. Upon detection, a read command request is output to the printer device 12 to request the issuance of a read command, and the address indicating the area in the output data area 5 in which the processing process 4 stores data is set as an access-prohibited area. The read command requesting means 7 registers the address in the access-prohibited address table 8, and the processing process 4 assigned to the CPU issues a data output command, thereby registering the processing process 4 in the timer queue 3, A read completion waiting means 9 for re-registering the corresponding process registered in the timer queue 3 in the queue 2 upon receiving a read completion notification from the printer device 12, and deleting the address related to the process from the access prohibited address table 8; , process abort means 10 for aborting a timed out process;
It includes data output means 11 at the hardware or firmware level that reads data from the output data area 5 and outputs it to the printer device 12 independently of the CPU when a read command is applied from the printer device 12.

The printer device 12 also includes output data information processing means 13 that receives a read command request from the read command request means 7 in the host computer 1 and recognizes the start address and hide number of data to be read; It includes a read command issuing means 14 for issuing a read command according to the start address and number of bytes recognized by the processing means 13, and a read completion notification means 15 for outputting a read completion notification indicating that data output has been completed. I'm here.

FIG. 2 is a flowchart 1 showing an example of processing by the host computer 1, and FIG. 3 is a flowchart 1 showing an example of processing by the printer device 12.The operation of this embodiment will be explained below with reference to each figure. do.

If the host computer 1 does not have a timed-out process in the timer queue 3 (step S2-1) and has not received the read completion notification (step S2-2),
Allocate the CPU to the process with the highest priority among the processes registered in queue 2 (Step S2-3
).

When the processing process 4 assigned to the CPU outputs data to the printer device 12, it refers to the access-prohibited address table 8 and outputs data to an area other than the access-prohibited area in the output data area 5 provided on the buffer. Store the output data and then issue the output command. When an output command is issued from the process 4 being processed, it is detected by the output processing occurrence detection means 6 (step S2-4).
When the output processing occurrence detection means 6 detects the issuance of an output command, the read command request means 7 requests the printer device 12 to issue a read command (the beginning of the output data stored in the output data area 5). (including address and Hyde number) (step S2-5), register the start address and end address of the area where the output data in the output data area 5 is stored in the access-prohibited address table 8, and Preventing the area from being accessed by the process (step S2-6);
The process 4 being processed is registered in the timer queue 3 (step S2-7).

When the output data information processing means 13 in the printer device 12 receives the read command request from the read command requesting means 7, it recognizes the start address and hide number contained therein (step S3-1).

The read command issuing means 14 is the output data information processing means 13
If the number of hides recognized is less than a predetermined size, the output data information processing means 13 issues a read command with the recognized start address and number of hides as the read start address and the number of bytes to read, and output data information processing is performed. If the number of hides recognized by the means 13 is greater than or equal to a predetermined size, first, the output data information processing means 13 reads the head address and predetermined size recognized by the output data information processing means 13 and uses them as a read start address and a read by I/number. Then, the predetermined size is added to the read start address in the previously issued read command as the read start address until the size of the unread data becomes less than the predetermined size. By issuing a read command that includes an address and having the predetermined size as the number of read hides, and when the size of the unread data becomes less than the predetermined size, the read start address is set as the read command that was previously issued. A read command is issued that includes an address obtained by adding the predetermined size to the read start address of , and includes the number of hides of data that has not been read as the number of hides read (step S
3-2. Step S3-3).

Every time a read command is applied from the printer f12, the data output means 11 in the host computer 1 reads data designated by the read command from the output data area 5 and adds it to the printer device 12.

When the data output is completed, the read completion notification means 15 in the printer device 12 informs the output data information processing means 13.
When data of the recognized number of bytes is sent from the host computer 1, a read completion notification is output to the host computer 1 (step S3-4).

Read completion waiting means 9 in host computer 1
When receiving the read completion notification from the printer device 12 (step S2-2), the corresponding address is deleted from the access-prohibited address table 8 and the address in the output data area 5 used by the process 4 for data output is deleted. To free up the area, step S2-9), and then re-register process 4, which was registered in timer queue 3, in queue 2 (
Step 52-10).

Further, if a read completion notification is not sent from the printer device 12 even after a predetermined period of time has passed since the process 4 was registered in the timer queue 3, the read completion waiting means 9 sends a message to that effect (step S2-1). The process abort means IO is notified, and the process abort means 10 that receives this notification aborts the process 4 registered in the timer queue 3 and deletes the address related to this process 4 registered in the access prohibited address table 8. (Step S2-8).

〔Effect of the invention〕

As explained above, in the present invention, when a process assigned to a CPU issues an output command, the process is registered in a timer queue, and the process outputs data storing output data to an output device. The information indicating the area in the area is prohibited from access as the information indicating the prohibited area, and is stored in the information table. When the output of data to the blade device by the data output means is completed, the process registered in the timer queue is queued. At the same time as re-registering, the information about the process in the access prohibition information table is deleted and the area in the output data area used by the process for data output is released, so after the data output is completed. , the output data area can be immediately released, and the CPU can be allocated evenly to the CPU boundary process and the I10 boundary process.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a flowchart showing an example of processing by a host computer, and FIG. 3 is a flowchart showing an example of processing by a printer device. In the figure, 1... host computer, 2... queue, 3... timer queue, 4... processing process, 5... output data area, 6... output processing occurrence detection means , 7... Read command requesting means, 8... Access prohibited address table, 9... Read completion waiting means, 10... Process abort means, 11... Data outputting means, 12... Printer device , 13... Output data information processing means, 14... Read command issuing means, 15... Read completion notification means.

Claims (2)

[Claims] (1) A data output method in which data is output from a computer system to an output device, which has a queue in which multiple processes are registered, and determines the process to which a CPU is assigned based on the priority of each process registered in the queue. In the computer system, the computer system includes: an output data area in which data output by a process to an output device is stored; an access prohibition information table in which information indicating an access prohibited area in the output data area is registered; and the CPU By issuing an output command, the process assigned to the CPU sends a read command request to the output device and indicates an area in the data output area in which the process assigned to the CPU stores data. a read command requesting means for registering information in the access prohibition information table as information indicating an access prohibited area; and a process assigned to the CPU registers the process in a timer queue by issuing an output command; read completion waiting means for re-registering the process registered in the timer queue in the queue upon receiving a read completion notification from the device, and deleting information regarding the process from the access prohibition information table; and data output means for reading data stored in the output data area and outputting it to the output device in response to an instruction, the output device transmitting the read instruction to the data in response to the read instruction request. The process includes a read command issuing means for issuing a read command to the output means, and a read completion notification means for outputting a read completion notification when data reading is completed, A data output method characterized in that an output command is issued after referring to an access prohibition information table and storing data in an area other than the access prohibition area in the output data area. (2) If a read completion notification is not output from the output device even after a predetermined period of time has passed after registering a process in the timer queue, the computer system aborts the process registered in the timer queue and 2. The data output method according to claim 1, further comprising process abort means for deleting information regarding the process from the access prohibition information table.