JP2011048590A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming device that maintains effectiveness of a memory and suppresses an influence of GC on the performance of equipment. <P>SOLUTION: When a factor of changing the size of a heap region 303 such as an insufficient memory error or addition/deletion of Java (R) application is detected, the size of the heap region 303 can be changed to secure a proper heap region 303 according to a condition of a multi-function machine in a Java (R) operation environment. Effectiveness of the memory can be maintained and an influence of GC on the performance of the multi-function machine can be suppressed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

  In a system equipped with Java (registered trademark), memory management is double management. One is memory management by an OS (Operating System). For memory management by the OS, only frequently used programs are placed in real memory for large programs, and those that are used infrequently are saved in an auxiliary storage device such as an HDD (Hard Disk Drive) by swap processing. We use effectively. Therefore, according to the memory management by the OS, there is no apparent memory shortage.

  The other is memory management by Java (registered trademark) on the OS. In memory management by Java (registered trademark), in the heap area, which is a use space for executing a Java (registered trademark) program, an area that is no longer used for program execution or a gap between areas used for program execution The memory is effectively used by a management mechanism called garbage collection (hereinafter referred to as GC) that collects these areas and increases the areas that can be used by other programs (refer to Patent Document 1).

  By the way, in the memory management by GC, when there is no area for executing a program in the heap area, the memory is exhausted and an error “Out Of Memory” occurs. In a device with abundant memory such as a personal computer, a large heap area for executing a Java (registered trademark) program can be secured. In an embedded device such as an image forming apparatus, a Java (registered trademark) is available. Since memory resources for executing the program are limited, when a plurality of Java (registered trademark) programs are started in a Java (registered trademark) operating environment, an error occurs due to insufficient memory, and the Java (registered trademark) ) There is a problem that the program cannot be used.

  In addition, there is a method of increasing the heap area in order to start a plurality of Java (registered trademark) programs in the Java (registered trademark) operating environment. However, the larger the heap area, the longer the processing time required for GC. Thus, there is a problem of affecting the performance of the device.

  Furthermore, there is a method to increase / decrease the heap area to an optimum size for execution of the Java (registered trademark) program depending on the configuration of the embedded device, such as adding memory. However, while the Java (registered trademark) program is running, There is a problem that the size cannot be changed.

  The present invention has been made in view of the above, and an object of the present invention is to provide an image forming apparatus capable of maintaining the effectiveness of a memory and suppressing the influence of GC on the performance of a device.

  In order to solve the above-described problems and achieve the object, the present invention provides a detection unit that detects occurrence of a change factor of a size of a heap area used for execution of an application among memory areas of a storage medium, And changing means for changing the size of the heap area in the memory area when occurrence of the change factor is detected by the detecting means.

  According to the present invention, in the Java (registered trademark) operating environment, the heap area can be appropriately secured according to the state of the embedded device, so that it is possible to maintain the effectiveness of the memory and to influence the device performance by the GC. There is an effect that it can be suppressed.

FIG. 1 is a block diagram illustrating a hardware configuration of the multifunction peripheral according to the present embodiment. FIG. 2 is a functional block diagram showing the configuration of the software program executed by the controller unit. FIG. 3 is a diagram showing an arrangement of memory areas in the RAM allocated to each program of the software program. FIG. 4 is a diagram illustrating a state in the heap area. FIG. 5 is a block diagram showing a characteristic functional configuration provided in the multifunction peripheral according to the present embodiment. FIG. 6 is a diagram showing the arrangement of the memory areas in the RAM after increasing the size of the heap area. FIG. 7 is a diagram for explaining the influence on the performance of the multifunction device due to the change in the size of the heap area. FIG. 8 is a diagram showing the arrangement of the memory areas in the RAM when the RAM area is expanded. FIG. 9 is a diagram illustrating an application definition file used for calculating the size of the heap area. FIG. 10 is a flowchart showing the flow of heap area size change processing when a Java (registered trademark) application is added or deleted. FIG. 11 is a flowchart showing a flow of processing for changing the size of the heap area when a memory shortage error occurs.

  Exemplary embodiments of an image forming apparatus according to the present invention will be explained below in detail with reference to the accompanying drawings. In the present embodiment, an example in which the image forming apparatus according to the present invention is applied to a multifunction peripheral capable of copying (copying) and printing will be described.

  FIG. 1 is a block diagram illustrating a hardware configuration of the multifunction peripheral according to the present embodiment. The multifunction device 1 according to the present embodiment includes a controller unit 100, an I / F group 107, an engine unit 108, an operation unit 109, an HDD (Hard Disk Drive) 110, and the like. The engine unit 108 controls an engine such as a printer for outputting an electrophotographic image. The operation unit 109 includes a touch panel and hard keys and functions as a user interface. The HDD 110 stores various software programs and the like. The I / F group 107 connects the controller unit 100 and the HDD 110, and is, for example, a USB (Universal Serial Bus), a network, an S-ATA (Serial Advanced Technology Attachment), or the like.

  The controller unit 100 is a motherboard on which a software program is executed, and via a chipset 102, a CPU (Central Processing Unit) 101, a RAM (Random Access Memory) 103, a ROM (Read Only Memory) 104, an ASIC (Application Specific Integrated Circuit) A105 and ASIC B106 are connected.

  The ROM 104 is a read-only memory that stores an OS (Operating System) and the like. The CPU 101 is a main part of the controller unit 100, and centrally controls each unit by executing a software program 200 (see FIG. 2) stored in the HDD 110 and the ROM 104. The RAM 103 is a storage medium having a memory area for the CPU 101 to execute the software program 200 (see FIG. 2). ASIC A 105 and ASIC B 106 perform communication control with the engine unit 108 and the operation unit 109, respectively.

  FIG. 2 is a functional block diagram showing the configuration of the software program executed by the controller unit. The software program 200 executed by the controller unit 100 (CPU 101) includes a multitasking UNIX (registered trademark) -based OS 201 in order to realize a plurality of functions of the multifunction device 1. The MFP 1 according to the present embodiment incorporates a JVM (Java (registered trademark) Virtual Machine) 202 by the OS 201. A Java (registered trademark) control processing program 203 that activates a Java (registered trademark) application A 204, a Java (registered trademark) application B 205, and a Java (registered trademark) application C 206, which will be described later, exists on the JVM 202. Note that the Java (registered trademark) control processing program 203 is called a multi-VM and may be included in the JVM 202.

  A Java (registered trademark) application 210 (Java (registered trademark) application A 204, Java (registered trademark) application B 205, and Java (registered trademark) application C 206) performs a plurality of processes in parallel on the JVM 202 by multithreading. Multi operation is realized. This multi-operation is assumed to be managed by the JVM 202. Further, the Java (registered trademark) application 210 is a plug-in that is added or deleted in order to expand or reduce the function of the software program 200.

  In addition to the JVM 202, the MFP 1 according to the present embodiment incorporates a native control processing program 207 for controlling hardware and controlling / managing resources of the MFP 1. The native control processing program 207 includes a network control program that controls communication with a network, an image data processing program that performs image processing on image data, and the like. Further, the native control processing program 207 includes a heap memory management controller 208 that realizes a characteristic function provided in the multifunction machine 1 according to the present embodiment. Note that the native control processing program 207 and the Java (registered trademark) operating environment 211 (JVM 202, Java (registered trademark) control processing program 203, Java (registered trademark) application 210) perform a plurality of processes by multitasking as viewed from the OS 201. Multi-operations performed in parallel are realized.

  Here, the arrangement of the memory areas in the RAM 103 allocated to each program of the software program 200 executed by the CPU 101 will be described with reference to FIG. FIG. 3 is a diagram showing an arrangement of memory areas in the RAM allocated to each program of the software program.

  The memory area in the RAM 103 includes an image processing area 305 that handles image data for which the native control processing program 207 (image data processing program) performs image processing, an OS control area 301 for executing the OS 201, and a native control processing program 207. It has a native program area 304 for execution and a Java (registered trademark) operation area 302 for executing a program (Java (registered trademark) operating environment 211) related to Java (registered trademark).

  The Java (registered trademark) operation area 302 has a heap area 303 used for executing the Java (registered trademark) application 210. It is assumed that the heap area 303 is managed under the jurisdiction of the JVM 202.

  Here, the state in the heap area 303 will be described with reference to FIG. FIG. 4 is a diagram illustrating a state in the heap area. When the Java (registered trademark) application A 204, the Java (registered trademark) application B 205, and the Java (registered trademark) application C 206 are executed by the CPU 101, the Java (registered trademark) application area 302 in the Java (registered trademark) operation area 302 has Java ( (Registered trademark) application area A 401, Java (registered trademark) application area B 402, and Java (registered trademark) application area C 403 are provided. The Java (registered trademark) application area A401 corresponds to the Java (registered trademark) application A204, the Java (registered trademark) application area B402 corresponds to the Java (registered trademark) application B205, and the Java (registered trademark) application area C403. Corresponds to the Java (registered trademark) application C206.

  In the heap area 303 in the Java (registered trademark) operation area 302, the sizes of the Java (registered trademark) application area A401, the Java (registered trademark) application area B402, and the Java (registered trademark) application area C403 are shown in FIG. As shown, it varies from application to application. Further, no more Java (registered trademark) application 210 can be added in the heap area 303 shown in FIG. If a new Java (registered trademark) application 210 is added, the JVM 202 detects the occurrence of a memory shortage error (Out Of Memory) due to a shortage of the heap area 303, and the Java (registered trademark) application 210 being executed is detected. All stop.

  Conventionally, when the occurrence of a memory shortage error is detected by the JVM 202, one of the currently executing Java (registered trademark) application A204, Java (registered trademark) application B205, and Java (registered trademark) application C206 is deleted. A new Java (registered trademark) application 210 had to be added. Alternatively, there may be a case where the area that can be used by the new Java (registered trademark) application 210 can be increased by garbage collection (GC). These are processes that cannot be avoided as long as the size of the heap area 303 is fixed.

  Therefore, in this embodiment, the size of the heap area 303 is made variable by the heap memory management controller unit 500 (see FIG. 5) realized by the heap memory management controller 208 included in the native control processing program 207, so that the multifunction device 1 The size of the heap area 303 is changed depending on the state.

  Next, among the functions that the software program 200 (heap memory management controller 208) illustrated in FIG. 2 causes the CPU 101 to execute, characteristic functions provided in the multifunction machine 1 according to the present embodiment will be described with reference to FIG. . FIG. 5 is a block diagram showing a characteristic functional configuration provided in the multifunction peripheral according to the present embodiment.

  As shown in FIG. 5, the multifunction device 1 includes a heap size management control unit 501, a JVM start / end control unit 502, a Java (registered trademark) application / suspend / resume / stop control unit 503, and an operating environment save / restore control. A heap memory management controller unit 500 including a unit 504 and the like. Note that since the change in the size of the heap area 303 is actually a change in the Java (registered trademark) operating environment 211 itself, the heap memory management controller unit 500 controls the JVM 202 itself.

  The JVM activation / termination control unit 502 controls the operation (activation and termination) of the JVM 202. In the Java (registered trademark) operating environment 211, the size of the heap area 303 must be set when the JVM 202 is activated. Therefore, in the present embodiment, it is necessary to place control of the operation of the JVM 202 under the management of the JVM start / end control unit 502.

  When the occurrence of a memory shortage error is detected by the JVM 202, the Java (registered trademark) application suspend / resume / stop control unit 503 instructs each Java (registered trademark) application 210 to perform self-save or a memory shortage error occurs. After the Java (registered trademark) operating environment is restored by the cancellation, each Java (registered trademark) application 210 is instructed to self-return.

  When the occurrence of a memory shortage error is detected, the operating environment save / restore control unit 504 saves the area used for execution of the JVM 202 and the heap memory management controller 208 from the heap area 303, and the JVM 202 and heap The area used for execution of the memory management controller 208 is returned to the heap area 303.

  The heap size management control unit 501 (detection means) generates a cause for changing the size of the heap area 303, such as a memory shortage error detected by the JVM 202, or addition or deletion of the Java (registered trademark) application 210 via the JVM 202. Is detected.

  Further, the heap size management control unit 501 (changing unit) changes the size of the heap area 303 when a factor for changing the size of the heap area 303 is detected. More specifically, when the heap size management control unit 501 detects a memory shortage error as an occurrence of a change in the size of the heap area 303, an unexpected use of memory or a temporary memory leak has occurred. Therefore, the memory shortage error can be avoided by increasing the size of the heap area 303. In addition, when the heap size management control unit 501 detects addition or deletion of the Java (registered trademark) application 210 as an occurrence of a change factor of the size of the heap area 303, the Java (registered trademark) in the heap area 303 at this time Since it can be seen that the area used to execute the application 210 increases or decreases, the size of the heap area 303 is increased or decreased. It is assumed that the heap size management control unit 501 changes the size of the heap area for each preset reference size when a factor for changing the size of the heap area 303 is detected.

  FIG. 6 is a diagram showing the arrangement of the memory areas in the RAM after increasing the size of the heap area. When a heap size management control unit 501 causes a change in the size of the heap area 303 (for example, a memory shortage error, the addition of a Java (registered trademark) application 210), as shown in FIG. And the heap area 303 is increased by the memory area indicated by reference numeral 601. Then, by increasing the size of the heap area 303, it is possible to avoid a memory shortage error and avoid a memory shortage by adding the Java (registered trademark) application 210. Since the native program area 304 is under the management of the OS 201, when the remaining memory area in the native program area 304 is reduced, the OS 201 performs SWAP processing (see FIG. 7), which is a function of the OS 201. By executing this, a memory shortage in the native program area 304 is avoided.

  As described above, by avoiding a memory shortage error or a memory shortage by adding the Java (registered trademark) application 210, an error does not occur as a whole of the multifunction device 1, and a functional problem of the multifunction device 1 occurs. Generation can be eliminated. However, when the memory shortage is avoided by increasing the size of the heap area 303, the performance of the MFP 1 is affected depending on the frequency of the SWAP processing. Note that there is no problem as long as the influence of the performance on the multifunction device 1 is within a range that can be accepted by the user.

  Next, the influence on the performance of the multifunction device 1 due to the change in the size of the heap area 303 will be described with reference to FIG. FIG. 7 is a diagram for explaining the influence on the performance of the multifunction device due to the change in the size of the heap area.

  When the size of the heap area 303 is changed, the heap size management control unit 501 performs garbage collection (hereinafter referred to as GC) that collects unused areas that are not used in the execution of the Java (registered trademark) application 210 in the heap area 303. ) Is generated arbitrarily. The time required for GC of the heap area 303 becomes longer as the GC range 701 (heap area 303) becomes larger. For this reason, when the size of the heap area 303 is increased, a time during which the multifunction device 1 is stopped by GC is generated, and the performance of the multifunction device 1 is degraded.

  Furthermore, since the reduced native program area 304 is under the management of the OS 201 as described above, the native control processing program 207 can be executed by executing the SWAP process even in a small memory area. However, since the SWAP process temporarily saves the contents stored in the native program area 304 in the HDD 110 as an auxiliary storage device or writes back the contents from the HDD 110 to the native program area 304, the process takes time. As a result, the performance of the multifunction device 1 is reduced.

  The heap size management control unit 501 (notification unit) urges the expansion of the memory area of the RAM 103 via the operation unit 109 on the basis of this performance degradation (for example, processing time required for GC or SWAP processing). Notification shall be made. For example, the heap size management control unit 501 makes a notification for urging the expansion of the memory area of the RAM 103 when the copy performance of the multi-function device 1 falls below the normal 80% due to the processing time required for the GC or SWAP processing. Alternatively, the heap size management control unit 501 increases the size of the heap area 303 with the addition of the Java (registered trademark) application 210, and the processing time required for GC is the processing time required for GC of a memory area of a predetermined size. When the number becomes twice or more, a notification for encouraging expansion of the memory area of the RAM 103 is made.

  Next, the arrangement of the memory area in the RAM 103 when the memory area of the RAM 103 is increased will be described with reference to FIG. FIG. 8 is a diagram showing the arrangement of the memory areas in the RAM when the RAM area is expanded. Similar to the memory area arrangement shown in FIG. 6, the memory area in the RAM 103 before the memory area expansion is reduced in the native program area 304 and the heap area 303 is increased by the memory area indicated by reference numeral 601. The memory area is arranged. On the other hand, the arrangement of the memory area in the RAM 103 after the expansion of the memory area is such that the memory area of the reduced native program area 304 returns to the original size (the size of the native program area 304 shown in FIG. 3), and the memory area of the heap area 303 Is maintained at the same size as before the expansion of the memory area. Note that it is possible to have more free areas in the native program area 304 and the heap area 303 by further expanding the memory area of the RAM 103.

  Next, an example of a method for calculating the size of the heap area 303 to be changed when occurrence of a change factor of the size of the heap area 303 is detected will be described with reference to FIG. FIG. 9 is a diagram illustrating an application definition file used for calculating the size of the heap area.

  When the occurrence of a change factor in the size of the heap area 303 is detected, the heap size management control unit 501 first starts the Java (registered trademark) from each Java (registered trademark) application area 901 arranged in the heap area 303. ) The Java (registered trademark) application 210 program size and data size corresponding to the application area 901, the memory capacity (heap usage amount) required to execute the Java (registered trademark) application 210 program, etc. The application definition file 902 including information regarding the registered trademark application 210 is read. Then, the heap size management control unit 501 calculates the size of the heap area 303 according to the read application definition file 902 of each Java (registered trademark) application 210.

  Specifically, the heap size management control unit 501 changes the size of the heap area according to the number of Java (registered trademark) applications 210 executed using the heap area 303. For example, by defining the reference size of the memory area in the heap area 303 used to execute one Java (registered trademark) application 210 as 10 MB, heap areas corresponding to the number of Java (registered trademark) applications 210 to be executed The size of 303 is calculated. Therefore, when three Java (registered trademark) applications 210 are executed, the size is changed to the 30 MB heap area 303.

  Further, the heap size management control unit 501 changes the size of the heap area 303 according to the number of effective functions among the functions of the Java (registered trademark) application 210 executed using the heap area 303. For example, by defining the reference size of the memory area in the heap area 303 used for executing one effective function as 2 MB, the heap area for the effective function of the Java (registered trademark) application 210 being executed The size of 303 is calculated. Accordingly, when the effective functions of the three Java (registered trademark) applications 210 are “5”, “6”, and “4”, respectively, the size is changed to the 30 MB heap area 303.

  Further, the heap size management control unit 501 changes the size of the heap area 303 in accordance with the total memory capacity indicated by the application definition file 902 of each Java (registered trademark) application 210 executed using the heap area 303.

  In the present embodiment, the heap size management control unit 501 adds a value calculated by adding the size calculated by the above calculation method and the size of the memory area necessary for executing the Java (registered trademark) operating environment 211. The size of the heap area 303 to be changed is calculated.

  Next, the flow of processing for changing the size of the heap area 303 when a Java (registered trademark) application 210 is added or deleted will be described with reference to FIG. FIG. 10 is a flowchart showing the flow of heap area size change processing when a Java (registered trademark) application is added or deleted.

  When the Java (registered trademark) application 210 is added or deleted (step S1001), the JVM 202 transmits a size change notification requesting the heap size management control unit 501 to change the size of the heap area 303. Then, the heap size management control unit 501 detects the addition or deletion of the Java (registered trademark) application 210 as the occurrence of the change factor of the size of the heap area 303, and the Java (registered trademark) application suspension / resume / suspend control unit. 503 terminates the currently executing Java (registered trademark) application 210 to restart the JVM 202 (step S1002). Subsequently, the JVM activation / termination control unit 502 terminates the JVM 202 (step S1003).

  Next, the heap size management control unit 501 calculates the size of the heap area 303 to be changed by using the method for calculating the size of the heap area 303 described above (step S1004). Note that an arbitrary calculation method is selected in advance as a method for calculating the size of the heap area 303. Next, the heap size management control unit 501 changes the size of the heap area 303 by redefining the calculated size of the heap area 303 in the startup setting of the JVM 202 (step S1005). Then, the JVM activation / termination control unit 502 activates the JVM 202 based on the re-defined activation setting of the JVM 202 (step S1006), and the Java (registered trademark) application suspension / resume / cancel control unit 503 performs Java (registration). (Trademark) application 210 is activated (step S1007).

  Next, a flow of processing for changing the size of the heap area 303 when a memory shortage error occurs will be described with reference to FIG. FIG. 11 is a flowchart showing a flow of processing for changing the size of the heap area when a memory shortage error occurs.

  When the JVM 202 detects the occurrence of a memory shortage error (step S1101), the JVM 202 transmits a size change notification requesting the heap size management control unit 501 to change the size of the heap area 303. Then, the heap size management control unit 501 detects a memory shortage error as the occurrence of a change factor of the size of the heap area 303, and the Java (registered trademark) application 210 that the operating environment save / restore control unit 504 is currently running. Is saved (step S1102).

  Here, the reason why the currently activated Java (registered trademark) application 210 is not terminated is that the heap area 303 is already insufficient, so that the currently activated Java (registered trademark) application 210 cannot be operated any more. Because. If the currently activated Java (registered trademark) application 210 is operated in order to terminate the currently activated Java (registered trademark) application 210, a memory shortage error further occurs. Therefore, in this embodiment, it is necessary to control saving of the Java (registered trademark) application 210 from other than the Java (registered trademark) operating environment 211 (operating environment save / restore control unit 504).

  When the saving of the currently activated Java (registered trademark) application 210 is completed, the JVM activation / termination control unit 502 terminates the JVM 202 (step S1103). Next, the heap size management control unit 501 calculates the size of the heap area 303 to be changed by using the above-described method for calculating the size of the heap area 303 (step S1104). In addition, the calculation method of the size of the heap area 303 may be an arbitrary calculation method (calculation according to the number of applications, calculation according to the number of effective functions, calculation according to the memory capacity, Select what percentage of the memory area the application is using, etc.). Next, the heap size management control unit 501 changes the size of the heap area 303 by redefining the calculated size of the heap area 303 in the startup setting of the JVM 202 (step S1105). Then, the JVM activation / termination control unit 502 activates the JVM 202 based on the re-defined activation setting of the JVM 202 (step S1106), and the operating environment save / restore control unit 504 activates the Java (registered trademark) application 210. Return (step S1107).

  As described above, according to the MFP 1 according to the present embodiment, when a change factor of the size of the heap area 303 such as a memory shortage error or the addition or deletion of the Java (registered trademark) application 210 is detected, the heap area By changing the size of 303, the heap area 303 can be appropriately secured in the Java (registered trademark) operating environment in accordance with the state of the multifunction device 1, so that the validity of the memory is maintained and the multifunction device by GC is used. The influence on the performance of 1 can be suppressed.

  In the above embodiment, the image forming apparatus according to the present invention is described by taking an example in which the image forming apparatus is applied to a multifunction machine having at least two functions among a copy function, a printer function, a scanner function, and a facsimile function. The present invention can be applied to any image forming apparatus such as a printer, a scanner apparatus, and a facsimile apparatus.

1 MFP 103 RAM
204 Java (registered trademark) application A
205 Java (registered trademark) application B
206 Java (registered trademark) application C
210 Java (registered trademark) application 303 Heap area 501 Heap size management control unit 902 Application definition file

Japanese Patent No. 4170988

Claims (8)

Detecting means for detecting occurrence of a change factor of a size of a heap area used for executing an application among memory areas of a storage medium;
Changing means for changing the size of the heap area in the memory area when occurrence of the change factor is detected by the detecting means;
An image forming apparatus comprising:   The image forming apparatus according to claim 1, wherein the detection unit detects addition or deletion of the application as occurrence of the change factor.   The image forming apparatus according to claim 1, wherein the detection unit detects a memory shortage error due to a shortage of the heap area as the occurrence of the change factor.   The changing means changes the size of the heap area according to the number of the applications to be executed using the heap area when the addition or deletion of the application is detected as the occurrence of the change factor. The image forming apparatus according to claim 2.   The changing means detects the addition or deletion of the application as the occurrence of the change factor, and the heap according to the number of effective functions among the functions of the application executed using the heap area. The image forming apparatus according to claim 2, wherein the size of the area is changed. In the heap area, an application definition file indicating a memory capacity necessary for executing each application to be executed is stored,
The change unit changes the size of the heap area according to the total memory capacity indicated by the application definition file of each application to be executed when the addition or deletion of the application is detected as the occurrence of the change factor. The image forming apparatus according to claim 2.   The change means changes the size of the heap area for each preset reference size when the memory shortage error is detected as the occurrence of the change factor. An image forming apparatus according to claim 1.   It further comprises notification means for notifying the expansion of the memory area of the storage medium based on the processing time required for garbage collection or SWAP processing of the heap area after changing the size of the heap area. The image forming apparatus according to claim 1.

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