Image forming apparatus

Abstract

To provide an image formation apparatus capable of efficiently preventing an occurrence of errors during writing of data into a storage unit where the number of times of rewriting is restricted.SOLUTION: An image formation apparatus includes a storage unit 60 in which the number of times of rewriting is restricted, and a control unit 10. The control unit 10 serves as a first writing unit that performs writing of temporary data into the storage unit 60 before writing operation to the storage unit 60, a determination unit that determines whether a region in which actual data can be written remains in the storage unit 60 based on a writing result of the temporal data, and a second writing unit that performs writing of actual data into the storage unit 60 when the determination unit determines that a region in which the actual data can be written in the storage unit 60 remains.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an image forming apparatus.

Background Art

[0002] Conventionally, an image forming apparatus including an SSD (Solid State Drive) as a storage device for storing data such as image data has been known. The SSD has a lifespan due to write endurance. When this lifespan is reached, the SSD can be read but cannot be written. In this case, it is detected that the lifespan has been reached only when writing to the SSD occurs.

[0003] In relation to this, Patent Document 1 describes an invention in which, in a data storage control device in which a plurality of types of memories having different write guarantee counts coexist, when the write count of the first non-volatile memory exceeds a predetermined count, the second non-volatile memory is used. Further, Patent Document 2 describes an invention in which the type of data to be backed up to an external device is switched according to whether the failure of the non-volatile memory is a read error or a write error.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the technique described in Patent Document 1, since the predetermined count, which is the write count threshold, varies for each non-volatile memory, there is a problem that if the threshold is set constant, it cannot cope with this variation. Furthermore, with the technology described in Patent Document 2, a failure in the non-volatile memory is only discovered when a write or read error occurs. Therefore, if an error occurs in the middle of a job, data may be lost or the job may have to be reloaded to compensate for the lost data, resulting in a decrease in device performance.

[0006] An object of the present invention is to provide an image forming apparatus capable of efficiently preventing the occurrence of errors during writing of data to a storage unit in which the number of times of rewriting is limited. [Means for solving the problem]

[0007] In order to solve the above problem, the image forming apparatus according to the invention described in claim 1 comprises: A storage unit that has a limited number of times that it can be rewritten; a determination unit that determines whether an area remains in the storage unit to which provisional data and real data can be written before a write operation to the storage unit; a first writing unit that writes the provisional data to the storage unit when the determining unit determines that an area remains in the storage unit to which the provisional data and the real data can be written; a second writing unit that writes the real data to the storage unit when the writing of the provisional data by the first writing unit is successful; Equipped with The first writing unit, before writing the temporary data , before Writing of provisional data and said actual data transfer the data stored in the write access destination so that the data becomes empty at the write access destination within the memory corresponding to the number corresponding to the data size Performing data evacuation and determining whether the data evacuation was successful; when it is determined that the data backup is successful, write the temporary data to the write access destination where the data is in an empty state The image forming apparatus further includes a control unit that, when it is determined by the first writing unit that the data saving has failed, stores the original data in a second storage unit and transitions to a restricted mode in which an image forming process is executed.

[0008] The invention described in claim 2 is the image forming apparatus described in claim 1, The data size of the provisional data is smaller than the data size of the main data.

[0009] The invention according to claim 3 is the image forming apparatus according to claim 1 or 2, wherein the first writing unit writes the temporary data in the minimum unit of write access in the storage unit.

[0010] The invention according to claim 4 is the image forming apparatus according to any one of claims 1 to 3, wherein the first writing unit when the job received by the image forming apparatus includes a job with a different image data size for each job, when the job received by the image forming apparatus includes a job including header information that changes according to the number of pages, or immediately before the copy operation in the image forming apparatus performs writing of the temporary data thereto.

[0011] The invention according to claim 5 is the image forming apparatus according to any one of claims 1 to 4, wherein the control unit when the determination unit determines that there is no remaining area in the storage unit the temporary data and wherein the main data can be written, the main data is stored in a second storage unit, and the process proceeds to a restricted mode in which image forming processing is executed. Yes.

[0012] The invention according to claim 6 is the image forming apparatus according to claim 5, wherein in the restricted mode, when a first condition is satisfied, the control unit stores the main data in a memory as the second storage unit, and when a second condition is satisfied, the control unit stores the main data in an external storage as the second storage unit.

[0014] Claim 7 The invention described in 6 is the image forming apparatus according to any one of claims 1 to wherein the first writing unit calculates a data size required for writing the main data, and if the calculated data size spans a plurality of access destinations in the storage unit, the first writing unit writes the temporary data to the plurality of access destinations.

[0015] Claim 8 The invention described in 7 is the image forming apparatus according to When the data size required for writing the book data is a fixed size, the first writing unit applies the fixed size to the calculation of the data size required for writing the book data. When the size is variable, the worst size is applied to the calculation.

[0016] Control unit 9 The invention described in claim 1 to 8 In the image forming apparatus according to any one of The first writing unit is configured to write the temporary data when the ratio of the current number of rewrites to the maximum number of rewrites of the storage unit is equal to or greater than a predetermined threshold value.

Effect of the Invention

[0017] According to the present invention, it is possible to efficiently prevent the occurrence of errors during writing of data to a storage unit whose write count is limited.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples.

[0020] (Configuration of Image Forming Apparatus) Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a front view for explaining an overview of the overall configuration of the image forming apparatus 1 according to the present embodiment.

[0021] The image forming apparatus 1 of the present embodiment is an MFP (Multifunction Peripheral) that performs color image formation by an electrophotographic method. As shown in FIG. 1, the image forming apparatus 1 includes a housing 1a, an operation display unit 30 (see FIG. 2) provided outside the housing 1a, a scanner 40 provided on the upper part of the housing 1a, and a paper discharge unit 70 exposed outside the housing 1a below the scanner 40. The image forming apparatus 1 executes a predetermined process according to an input operation received by the operation display unit 30. Further, the scanner 40 executes a process of reading an image formed on a sheet (recording medium).

[0022] In addition, the housing 1a is provided with an openable and closable paper feed tray 81 which is a paper feed unit 80, an openable and closable manual feed tray 82, and the like. Inside the housing 1a, an image forming unit 20 for forming an image on a sheet is provided.

[0023] The image forming unit 20 forms an image on a sheet supplied from the paper feed tray 81 or the manual feed tray 82 and discharges it to the paper discharge unit 70. The image forming unit 20 includes an image carrier 21 which is a drum-shaped photoreceptor that supports an electrostatic latent image on its surface, a cleaning unit 22 that removes residual toner on the surface of the image carrier 21, a charging roller 23 that uniformly charges the surface of the image carrier 21, an exposure unit 24 that exposes the surface of the charged image carrier 21 to form an electrostatic latent image, a developing unit 25 that develops the electrostatic latent image using a developer containing toner to form a toner image on the surface of the image carrier 21, a transfer unit 26 that primarily transfers the formed toner image to an intermediate transfer belt 261 in a transfer area and then secondarily transfers it from the intermediate transfer belt 261 to a sheet, a fixing unit 27 that fixes the toner image on the sheet, and a conveyance unit 28 having a plurality of conveyance rollers that convey a sheet in a conveyance path from the paper feed tray 81 or the manual feed tray 82 to the paper discharge unit 70. Among the above, the image carrier 21, the cleaning unit 22, the charging roller 23, the exposure unit 24, and the developing unit 25 constitute an image forming unit.

[0024] Four image forming units are provided corresponding to the four colors of Y (Yellow), M (Magenta), C (Cyan), and K (Black), and are arranged in the order of Y, M, C, K along the lower horizontal plane of the intermediate transfer belt 261. In each image forming unit, a cleaning unit 22, a charging roller 23, an exposure unit 24, and a developing unit 25 are arranged in this order along the outer peripheral surface of the image carrier 21.

[0025] The image carrier 21 rotates about a predetermined rotation axis. A photosensitive layer is formed on the outer peripheral surface of the image carrier 21.

[0026] The cleaning unit 22 has a flat cleaning blade made of an elastic body, and by bringing the cleaning blade into contact with the surface of the image carrier 21, foreign matters such as toner remaining on the surface of the image carrier 21 without being transferred to the intermediate transfer belt 261 are removed.

[0027] The charging roller 23 is a cylindrical member that contacts the surface of the image carrier 21 and rotates passively about a predetermined rotation axis as the image carrier 21 rotates. When a charging drive voltage is applied to the charging roller 23 from a power supply unit (not shown), the surface of the image carrier 21 is uniformly charged.

[0028] The exposure unit 24 includes an LD (Laser Diode) as a light emitting element, and exposes the surface of the image carrier 21 charged by the charging roller 23 by irradiating laser light, thereby forming an electrostatic latent image on the image carrier 21.

[0029] The developing unit 25 includes a developing sleeve (developing roller) arranged to face the surface of the image carrier 21. The developing unit 25 supplies a developer containing toner supplied from a toner bottle (not shown) to the surface of the developing sleeve having a predetermined developing bias potential, so that the toner in the developer adheres from the surface of the developing sleeve to the electrostatic latent image on the surface of the image carrier 21, thereby forming a toner image on the surface of the image carrier 21.

[0030] The transfer unit 26 includes two belt conveyance rollers 262, four primary transfer rollers 263 arranged to face each image carrier 21, an intermediate transfer belt 261 spanned around the belt conveyance rollers 262 and the primary transfer rollers 263, a belt cleaning unit 264 for removing toner remaining on the intermediate transfer belt 261, and a secondary transfer roller 265 that is urged against one of the belt conveyance rollers 262 and rotates passively as the belt conveyance roller 262 rotates. In the transfer unit 26, with a bias voltage of the opposite polarity to the toner applied to the primary transfer roller 263, the intermediate transfer belt 261 rotates in a circumferential direction, so that the toner is transferred from the surface of the rotating image carrier 21 to the intermediate transfer belt 261. Further, after the toners of each color of Y, M, C, and K are superimposed and transferred, the paper passes between the secondary transfer roller 265 to which a predetermined bias voltage is applied and the intermediate transfer belt 261, so that the color toner image is transferred from the intermediate transfer belt 261 to the paper. The toner remaining on the intermediate transfer belt 261 without being transferred to the paper is removed by the cleaning blade of the belt cleaning unit 264.

[0031] The fixing unit 27 heats and presses the paper onto which the toner image has been transferred to fix the toner image on the paper. The fixing unit 27 includes a pair of rollers including a heating roller and a pressure roller that sandwich the paper. The paper onto which the toner image has been fixed is conveyed by the conveying unit 28 and sent out to the paper discharge unit 70.

[0032] The scanner 40 has an image reading unit 41 provided at the upper part of the housing 1a, an ADF 42 (Auto Document Feeder) provided at the upper part of the image reading unit 41, and a sensor 43 (not shown). The image reading unit 41 includes a platen glass 411 that constitutes a placement surface 41a on which the paper is placed, an optical system such as a light source and a reflector for irradiating light from the placement surface 41a side to the paper on the placement surface 41a, and an image sensor for detecting the light irradiated from the optical system and reflected by the paper. Under the control of the control unit 10, the image reading unit 41 reads an image of the paper placed on the placement surface 41a of the platen glass 411, generates image data in bitmap format for each color of R (red), G (green), and B (blue), and stores it in the storage unit 60 (see FIG. 2). The ADF 42 conveys one by one the hand-fed document (recording medium on which the image to be read is formed) and causes the image reading unit 41 to read it. Further, the ADF 42 is moved within a movable range between a state of covering the placement surface 41a and a state of exposing the placement surface 41a by a user's operation. The sensor 43 measures the number of pages of the document set in the ADF 42 and the paper size of the document, and outputs the measurement result to the control unit 10 described later.

[0033] The paper discharge unit 70 shown in FIG. 1 is exposed to the outside of the housing 1a below the scanner 40 and within the range of the housing 1a, and the paper on which the image is formed by the image forming unit 20 is discharged in a state where it can be taken out by the user.

[0034] FIG. 2 is a block diagram showing the functional configuration of the image forming apparatus 1 of the present embodiment. The image forming apparatus 1 includes a control unit 10, an image forming unit 20, an operation display unit 30, a scanner 40, a communication unit 50, a storage unit 60, a paper discharge unit 70, a paper feeding unit 80, etc., and these units are connected via a bus. In the following, the description of the configurations already described will be omitted.

[0035] The control unit 10 has a CPU 11 (Central Processing Unit) and a RAM 12 (Random Access Memory). The CPU 11 reads out and executes the programs stored in the storage unit 60, and performs various arithmetic processes. The RAM 12 provides a working memory space for the CPU 11 and stores temporary data.

[0036] The operation display unit 30 includes an operation unit 31 and a display unit 32. The operation unit 31 is equipped with a touch panel formed to cover the display screen of the display unit 32, various operation buttons such as numeric buttons and start buttons, and outputs an operation signal based on the user's operation to the control unit 10. The display unit 32 is composed of an LCD (Liquid Crystal Display) and displays various screens according to the instructions of the display signal input from the control unit 10.

[0037] The communication unit 50 is composed of a network card or the like. The communication unit 50 is connected to a communication network such as a LAN (Local Area Network) and performs information transmission and reception with external devices (external storage such as a second storage unit) on the communication network. The control unit 10 communicates with external devices on the communication network via the communication unit 50.

[0038] The storage unit 60 is a non-volatile memory composed of an SSD (Solid State Drive). The storage unit 60 stores image data acquired by the scanner 40, job data including image data input from the outside via the communication unit 50, and various setting data. In addition, the storage unit 60 stores various programs and setting data executed by the CPU 11.

[0039] The control unit 10 having these CPU 11 and RAM 12 comprehensively controls each part of the image forming apparatus 1 according to the program stored in the storage unit 60. For example, the control unit 10 operates each part of the image forming unit 20 based on the image data and job data stored in the storage unit 60 to form an image on a sheet of paper. Also, the control unit 10 operates each part of the scanner 40 based on a user operation to read an image of a document, and stores the obtained image data in the storage unit 60 or transmits it by FAX via the communication unit 50.

[0040] Further, before the writing operation to the storage unit 60, the control unit 10 performs writing of temporary data to the storage unit 60. Here, the control unit 10 functions as a first writing unit. The temporary data is predetermined data set in advance, and the data size of the temporary data is smaller than the data size required for writing the main data described later.

[0041] Further, the control unit 10 determines whether an area where the main data can be written remains in the storage unit 60 based on the writing result of the temporary data. Here, the control unit 10 functions as a determination unit. The main data is data written to the storage unit 60 when the control unit 10 receives a job via the communication unit 50, when the job includes jobs with different image data sizes for each job, when the job includes header information that changes according to the number of pages, or immediately before a copy operation.

[0042] Further, when the determination unit determines that an area where the main data can be written remains in the storage unit 60, the control unit 10 performs writing of the main data to the storage unit 60. Here, the control unit 10 functions as a second writing unit.

[0043] Further, when the determination unit determines that no area where the main data can be written remains in the storage unit 60, the control unit 10 stores the main data in the RAM 12 or the like as a second storage unit, and shifts to a restricted mode in which image formation processing is executed.

[0044] (Operation of the image forming apparatus 1) Next, the operation of the writing inspection process of the present embodiment will be described. FIG. 3 shows a flowchart of the writing inspection process executed in the image forming apparatus 1. The writing inspection process is executed in cooperation with the control unit 10 and a program stored in the storage unit 60.

[0045] Since the failure rate of the SSD that constitutes the memory unit 60 increases as the usage rate increases, the write check process is performed when the usage rate of the memory unit 60 is equal to or higher than a preset threshold value (e.g., 90%). Also, since the write check process is a check on whether writing to the memory unit 60 is possible, when the control unit 10 receives a job via the communication unit 50 and the job includes jobs with different image data sizes for each job, when the job includes header information that changes according to the number of pages, or when the occurrence of the write operation of this data to the memory unit 60 is determined, such as immediately before the copy operation, the write check process is performed.

[0046] First, the control unit 10 calculates a write data size that combines the data size required for writing temporary data and the data size required for writing this data (step S1). Writing of temporary data is writing of temporary data to the memory unit 60 performed before writing of this data, and is performed in units of BLOCK, which is the minimum unit of write access in the memory unit 60. When calculating the data size required for writing this data, if the data size is a fixed size such as backup data, a preset fixed size is applied. Also, when the data size required for writing this data is a variable size, the worst size in the data amount per page is determined from the user's usage history. Then, the number of pages and the paper size of the original are obtained by accepting settings from the user via the operation display unit 30, or by using the results measured by sensing with the sensor 43 when the original is set on the scanner 40 during a copy operation or the like.

[0047] Next, the control unit 10 calculates the number of BLOCKs in the memory unit 60 required to write the data of the write data size calculated in step S1 to the memory unit 60 (step S2). Next, the control unit 10 determines whether the number of free BLOCKs in the memory unit 60 is larger than the number of BLOCKs required for writing calculated in step S2 (step S3). When the number of free BLOCKs is greater than the number of BLOCKs required for writing (step S3; YES), the control unit 10 performs data backup within the BLOCKs of the number of BLOCKs required for writing in the storage unit 60, and determines whether the data backup was successful (step S4). When the data backup is successful (step S4; YES), the control unit 10 writes temporary data to the BLOCK in which the data backup was performed in step S4, and determines whether the writing of the temporary data was successful (step S5). When the number of BLOCKs required for writing calculated in step S2 is plural, the control unit 10 writes temporary data to the plural BLOCKs. When the writing of the temporary data is successful (step S5; YES), the control unit 10 holds the writability of the main data (step S6), and ends the write inspection process. After the write inspection process ends, when the writability of the main data is held, the control unit 10 writes the main data to the storage unit 60.

[0048] Also, when the number of free BLOCKs is less than or equal to the number of BLOCKs required for writing (step S3; NO), when the data backup fails (step S4; NO), or when the writing of the temporary data fails (step S5; NO), the control unit 10 shifts to the restricted mode (step S7), and ends the write inspection process. In the restricted mode, the control unit 10 does not write the main data to the storage unit 60, but controls to enable the execution of the image forming process. For example, when performance is required, such as when used as a temporary storage destination for image processing performed in a copy operation or the like as the first condition, the control unit 10 backs up the data for writing the main data to the RAM 12 (second storage unit) in the control unit 10. Also, when performance is not required as compared with the first condition, such as when constantly replacing the data stored in the storage unit 60 as the second condition, the control unit 10 backs up the main data to an external storage (not shown) as the second storage unit via the communication unit 50.

[0049] As described above, the image forming apparatus 1 includes a storage unit 60 whose rewrite count is limited, a first writing unit (control unit 10) that writes temporary data to the storage unit 60 before the writing operation to the storage unit 60, a determination unit (control unit 10) that determines whether an area where main data can be written remains in the storage unit 60 based on the writing result of the temporary data, and a second writing unit (control unit 10) that writes the main data to the storage unit 60 when the determination unit determines that an area where main data can be written remains in the storage unit 60. Therefore, it is possible to efficiently prevent the occurrence of an error during the writing of data to the storage unit 60 whose rewrite count is limited.

[0050] Further, in the image forming apparatus 1, since the data size of the temporary data is smaller than the data size of the main data, it is possible to minimize the reduction of the free area of the storage unit 60 due to the writing of the temporary data.

[0051] Further, in the image forming apparatus 1, since the first writing unit (control unit 10) writes the temporary data in the minimum unit of the writing access in the storage unit 60, it is possible to minimize the reduction of the free area of the storage unit 60 due to the writing of the temporary data.

[0052] Further, in the image forming apparatus 1, since the first writing unit (control unit 10) writes the temporary data when the occurrence of the writing operation of the main data to the storage unit 60 is determined, it is possible to prevent an error from occurring during the writing to the storage unit 60.

[0053] Further, in the image forming apparatus 1, when the determination unit (control unit 10) determines that no area where main data can be written remains in the storage unit 60, the control unit 10 that stores the main data in the second storage unit and shifts to the restricted mode in which the image forming process is executed is provided, so that the image forming apparatus 1 can be operated even when writing to the storage unit 60 cannot be performed.

[0054] In the image forming apparatus 1, when the first condition is applied in the restricted mode, the control unit 10 stores the main data in the memory (RAM 12) as the second storage unit, and when the second condition is applied, stores the main data in the external storage as the second storage unit. Therefore, even when writing to the storage unit 60 cannot be performed, the image forming apparatus 1 can be operated regardless of the performance requirements.

[0055] In the image forming apparatus 1, the first writing unit (control unit 10) secures an area necessary for writing the main data in the storage unit 60 when writing the temporary data, so that an error can be prevented from occurring during writing to the storage unit 60.

[0056] In the image forming apparatus 1, the first writing unit (control unit 10) calculates the data size necessary for writing the main data, and as a result of the calculation, when the data size straddles a plurality of access destinations in the storage unit 60, writes the temporary data to the plurality of access destinations, so that an error can be prevented from occurring during writing to the storage unit 60.

[0057] In the image forming apparatus 1, when the data size necessary for writing the main data is a fixed size, the first writing unit (storage unit 60) applies the fixed size to the calculation of the data size necessary for writing the main data, and when it is a variable size, applies the worst size to the calculation, so that an error can be prevented from occurring during writing to the storage unit 60.

[0058] In the image forming apparatus 1, the first writing unit (control unit 10) writes the temporary data when the usage rate of the storage unit 60 is equal to or higher than a predetermined threshold value, so that the writing inspection process of the storage unit 60 can be efficiently performed.

[0059] Note that the description in the above embodiment shows a preferred example of the image forming apparatus according to the present invention and is not limited thereto.

[0060] In the above-described embodiment, when the control unit 10 receives a job via the communication unit 50 and the job includes jobs with different image data sizes for each job, when the job includes header information that changes according to the number of pages, or when it is determined that a write operation to the storage unit 60 occurs immediately before a copy operation, the write inspection process is performed, but it is not limited to this. When it is determined that a write to the storage unit 60 will occur when the image forming apparatus 1 is powered off and then powered on again, the write inspection process may be performed when the power is turned off.

[0061] In the above-described embodiment, 90% is given as an example of the threshold value in the usage rate of the storage unit 60 for performing the write inspection process, but it is not limited to this. A value arbitrarily set by the user may also be used.

[0062] In the above-described embodiment, the minimum unit of the write access to the storage unit 60 is set to BLOCK, but it is not limited to this. A storage unit with a different unit as the minimum unit of the write access may also be used.

[0063] In addition, regarding the detailed configuration and detailed operations of the image forming apparatus, appropriate changes can be made within the scope not departing from the spirit of the present invention.

Explanation of Reference Numerals

[0064] 1 Image forming apparatus 10 Control unit (first writing unit, second writing unit, determination unit) 11 CPU 12 RAM (second storage unit) 20 Image forming unit 30 Operation display unit 40 Scanner 50 Communication unit 60 Storage unit 70 Paper discharge unit 80 Paper supply unit 81 Paper supply tray 82 Manual feed tray

Claims

1. A storage unit with a limited number of rewrites, a determination unit that determines whether an area where temporary data and main data can be written remains in the storage unit before the writing operation to the storage unit, a first writing unit that writes the temporary data to the storage unit when the determination unit determines that an area where the temporary data and the main data can be written remains in the storage unit, a second writing unit that writes the main data to the storage unit when the writing of the temporary data by the first writing unit is successful, comprising: Before writing the temporary data, the first writing unit performs data evacuation to transfer the data stored in the write access destination in the storage unit so that the data becomes empty at the number of write access destinations in the storage unit corresponding to the write data size of the temporary data and the main data, determines whether the data evacuation is successful, and when it is determined that the data evacuation is successful, writes the temporary data to the write access destination where the data is empty, An image forming apparatus further comprising a control unit that, when it is determined by the first writing unit that the data evacuation has failed, stores the main data in a second storage unit and shifts to a restricted mode in which image forming processing is executed.

2. The image forming apparatus according to claim 1, wherein the data size of the temporary data is smaller than the data size of the main data.

3. The image forming apparatus according to claim 1 or 2, wherein the first writing unit writes the temporary data in the minimum unit of write access in the storage unit.

4. The first writing unit writes the temporary data when the job received by the image forming apparatus includes jobs with different image data sizes for each job, when the job received by the image forming apparatus includes a job including header information that changes according to the number of pages, or immediately before the copy operation in the image forming apparatus. The image forming apparatus according to any one of claims 1 to 3.

5. The control unit stores the main data in a second storage unit and shifts to a restricted mode in which image forming processing is executed when the determination unit determines that an area where the temporary data and the main data can be written does not remain in the storage unit. The image forming apparatus according to any one of claims 1 to 4.

6. The image forming apparatus according to claim 5, wherein in the restriction mode, when the first condition is applied, the control unit stores the main data in a memory as the second storage unit, and when the second condition is applied, the control unit stores the main data in an external storage as the second storage unit.

7. The first writing unit according to any one of claims 1 to 6, wherein the first writing unit calculates a data size required for writing the main data, and when the calculated data size spans a plurality of access destinations in the storage unit, the first writing unit writes the temporary data to the plurality of access destinations.

8. The image forming apparatus according to claim 7, wherein when the data size required for writing the main data is a fixed size, the first writing unit applies the fixed size to the calculation of the data size required for writing the main data, and when the data size is a variable size, the first writing unit applies a worst-case size to the calculation.

9. The image forming apparatus according to any one of claims 1 to 8, wherein the first writing unit writes the temporary data when a ratio of a current number of rewrites to a maximum number of rewrites of the storage unit is equal to or greater than a predetermined threshold.

Images