JP2012185764A - Memory access processing system, control method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform processing on the memory access requested by a CPU.SOLUTION: A memory access processing system includes a memory management unit 150 which replaces virtual address of page of a memory module 110 that is under overheat state with virtual address of page of the memory module 110 that is not under overheat state so that, of pages of the plural memory modules 110, a page of the memory module 110 that is under overheat state is moved to a page of the memory module 110 that is not under overheat state.

Description

  The present invention relates to a memory access processing system, a control method, and a program. In particular, the present invention relates to a memory access processing system for processing a memory access requested by a CPU, a control method for controlling the memory access processing system, and a program for the memory access processing system.

  In Web services, securities transactions, and the like, in a low-latency data input / output by a large number of clients, a large number of nodes are connected via a network, and the main storage device is utilized as a faster memory storage. In such a technique, the capacity of the memory storage depends on the amount of memory modules that can be installed in each node. However, since the amount of memory modules that can be mounted on a node depends on the waste heat performance of the chassis, a large number of nodes are required to realize large-capacity memory storage in a group of computers with low waste heat performance. There was a problem.

  Also, a method of changing the memory access pattern of the application according to the heat generation state of the memory module is conceivable, but this method has a problem that existing assets cannot be utilized.

  By the way, Patent Document 1 discloses a new way to reduce power consumption by identifying and accessing an underutilized part of the memory, thereby reducing the harmful effects of such throttling or low power modes. Techniques that can be achieved are described.

JP 2007-133879 A

  However, the technology described in Patent Document 1 is to energize moderately in order to mitigate the effects of “throttling” of a certain type of memory or the delay of returning from the low power mode. Therefore, the above-described problem cannot be solved by the technique described in Patent Document 1.

  In order to solve the above problem, according to a first aspect of the present invention, there is provided a memory access processing system for processing a memory access requested by a CPU, wherein the memory module is in an overheated state among a plurality of memory module pages. In order to move the page of the memory module to the page of the memory module that is not in the overheated state, a memory management unit that replaces the virtual address of the page of the memory module that is in the overheated state and the virtual address of the page of the memory module that is not in the overheated state is provided.

  According to a second aspect of the present invention, there is provided a control method for controlling a memory access processing system that processes a memory access requested by a CPU. In order to move to the page of the memory module, a memory management stage is provided in which the virtual address of the page of the high-temperature memory module and the virtual address of the page of the low-temperature memory module are switched.

  According to a third aspect of the present invention, there is provided a program for a memory access processing system for processing a memory access requested by a CPU, wherein the memory access processing system is configured to store a high-temperature memory module among a plurality of memory module pages. In order to move the page to the page of the low-temperature memory module, the virtual memory functions as a memory management unit that exchanges the virtual address of the page of the high-temperature memory module and the virtual address of the page of the low-temperature memory module.

  In addition, as described above, the summary of the invention does not enumerate all necessary features of the present invention, and sub-combinations of these feature groups can also be the invention.

  As is apparent from the above description, according to the present invention, when determining the balance between the allowable operating temperature of each component and the exhaust heat so that the computer can operate normally, compared with a node having an equivalent cooling facility, Many memory modules can be installed. Further, according to the present invention, it is possible to improve the memory access throughput in the computer. In addition, according to the present invention, when incorporated in an operating system, the above effect can be obtained without requiring modification of an existing application.

It is a figure which shows an example of the utilization environment of the memory access processing system 100 which concerns on one Embodiment. 3 is a diagram illustrating an example of a heat distribution method for each page of the memory module 110. FIG.

  Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention according to the scope of claims, and are combinations of features described in the embodiments. Not all are essential to the solution of the invention.

  FIG. 1 shows an example of a usage environment of a memory access processing system 100 according to an embodiment. The memory access processing system 100 is a system that processes a memory access requested by the CPU 200.

  The memory access processing system 100 includes a plurality of memory modules 110a and 110b (hereinafter collectively referred to as memory modules 110), a plurality of temperature sensors 120a and 120b (hereinafter collectively referred to as temperature sensors 120), and a page movement determination device 130. , A page movement destination selection device 140 and a memory management unit 150. The temperature sensor 120 may be an example of a “temperature measurement unit” in the present invention. Further, the page movement determination device 130 may be an example of the “page movement determination unit” in the present invention. Further, the page movement destination selection device 140 may be an example of a “page movement destination selection unit” in the present invention. The memory management unit 150 may be an example of the “memory management unit” in the present invention.

  The memory module 110 has a plurality of semiconductor memory chips mounted on a substrate, wired, and provided with connection terminals for connection to a computer. The memory module 110a is electrically connected to the temperature sensor 120a and the memory management unit 150, respectively. Similarly, the memory module 110b is electrically connected to the temperature sensor 120b and the memory management unit 150, respectively.

 The temperature sensor 120a measures the temperature of the memory module 110a. Similarly, the temperature sensor 120b measures the temperature of the memory module 110b.

  The page movement determination device 130 determines whether or not the page of the memory module 110 that is in the overheated state should be moved to the memory module 110 that is not in the overheated state.

  The page movement destination selection device 140 selects which page of the memory module the memory module 110 in an overheated state should be moved to.

  The memory management unit 150 maps the physical addresses and virtual addresses of the pages of the memory modules 110a and 110b.

  Here, the memory module 110 and the temperature sensor 120 associated therewith are set in two sets, but the temperature sensor 120 is shared not by each memory module 110 but by a plurality of memory modules 110, or by each memory chip instead of each memory module 110. The same can be applied even if the sensor 120 is installed. Further, the memory movement unit handled by the page movement determination device 130 and the page movement destination selection device 140 is a page unit for convenience. However, any memory chip unit or memory module 110 unit can be used as long as it can be handled by the memory management unit 150. Applicable in size.

  The page movement determination device 130 uses the temperature sensor 120a that measures the temperature of the memory module 110a and the temperature sensor 120b that measures the temperature of the memory module 110b, so that the memory module 110a and the memory module 110b are predetermined normal. It monitors whether it is operating below the operating temperature. Here, the number of memory modules 110 is two, but this may be any number. The temperature sensors 120a and 101b may have a one-to-many relationship with the memory module 110.

  Next, it is assumed that the page movement determination device 130 has detected the memory module 110 operating near the normal operating temperature or above the normal operating temperature. Here, as an example, it is assumed that the memory module 110a exceeds the normal operating temperature. The page movement determination device 130 notifies the page movement destination selection device 140 that the memory module 110a is operating above the normal operating temperature. At this time, it is possible to notify which page on the memory module 110a is the main cause of heat generation. As a method of identifying the main cause of heat generation, it is estimated that a page with a large number of memory accesses per unit time is the main cause of heat generation, or a memory chip with large heat generation using a temperature sensor attached to each memory chip It can be estimated that the page corresponding to is the main cause of heat generation.

  The page movement destination selection device 140 selects a heat generation distribution destination of the memory module 110 a received from the page movement determination device 130. As an example of the selection method, a method of quantifying the heat generation status of the memory chip mapped in the physical address space of each memory module 110 and rearranging so that the heat generation status is equalized by each memory chip, etc. can be considered. .

  After the heat transfer distribution destination is determined by the page movement destination selection device 140, the page that is determined to be overheated by the page movement determination device 130 is write-protected by the memory management unit 150, and the page movement determination device 130 is overheated. The content of the page determined to be in is copied to the page of the heat distribution destination determined by the page movement destination selection device 140.

  At this time, when writing occurs in the area where writing is prohibited by the memory management unit 150, the information that can specify the written logical address and the contents thereof are recorded in the log area. When a read process occurs in an area for which writing is prohibited by the memory management unit 150, the log area is scanned first, and if there is data corresponding to the read area, it is returned. Returns the contents.

  When the content of the page determined to be in the overheated state by the page movement determination device 130 has been copied to the page of the heat distribution destination determined by the page movement destination selection device 140, the generation of heat determined by the page movement destination selection device 140 is completed. Assuming that the virtual address space of the page determined to be overheated by the page movement determination device 130 is allocated to the virtual address space of the distribution destination page, the change contents recorded in the above-described log area are changed. Write. In addition, during the operation, when a read process occurs in an area that is prohibited from being written by the memory management unit 150, information that can specify the logical address written in the log area as a new change and its contents are displayed. Record.

  When all the contents of the log area have been reflected on the page of the heat distribution destination determined by the page movement destination selection device 140, the virtual address space assigned to the page determined to be overheated by the page movement determination device 130 Are reassigned to the page of the heat distribution destination determined by the page movement destination selection device 140, and the write prohibition of the page determined to be in the overheated state by the page movement determination device 130 is cancelled.

  FIG. 2 shows an example of a heat distribution method for each page of the memory module 110. In FIG. 2, the concept of a heat value obtained by dividing the Kelvin value, which is the absolute value of the temperature of the memory chip, by a constant is introduced.

  The page movement determination device 130 monitors the temperature of the memory modules 1 to 4. The temperature of the memory chip constituting each memory module is digitized and expressed as a larger value as the temperature increases. Here, it expresses as a value of 1-4, and makes it a heat value. The total heat value of all the memory chips constituting each memory module is defined as the heat value of the memory module.

  When it is assumed that a memory module having a heat value exceeding 10 is in an overheated state, it can be determined that the memory module 3 is in an overheated state, so the page movement destination selection device 140 selects a heat generation distribution destination. . As a method for determining the heat generation distribution destination by the page movement destination selection device 140, memory modules excluding the overheated memory module 3 and having a low heat value of the entire memory module were selected as the distribution destination memory modules. Further, among the memory chips constituting the memory module, the memory module having the intermediate heat value is selected as the memory chip to be distributed. Here, the first memory chip from the left of the memory module 1 and the central memory chip of the memory module 2 are selected.

  Next, the memory chip on the left side of the memory module 3 and the memory chip on the center of the memory module 3 are write-protected, and the contents of the memory chip on the left side of the memory module 3 are transferred to the memory chip on the left side of the memory module 1. The contents are copied to the central memory chip of the memory module 2.

  When the copying is completed, the virtual address space assigned to the left memory chip of the memory module 3 is assigned to the left memory chip of the memory module 1, and the virtual address space assigned to the central memory chip of the memory module 3 is The memory module 2 is assigned to the central memory chip.

  Finally, the write prohibition of the memory chip on the left side of the memory module 3 and the center chip is canceled, and the process is terminated.

  The first effect is that a larger number of memory modules can be mounted in terms of thermal design than a node having equivalently equivalent cooling equipment. The reason is that by moving the overheated page to a memory module with sufficient thermal design, the heat source is made uniform so that the overheated memory module can be cooled to a normal operating temperature. This is because the memory module can be operated at a temperature within the normal operating range without having to lower the temperature, and there is a margin in thermal design.

  The second effect is to contribute to an improvement in memory access throughput in the computer. The reason is that when a memory module is in an overheated state, the memory module is often in a state where there are very many accesses. As a result, the memory access is distributed, which contributes to the improvement of the memory access throughput of the system.

  A third effect is that the first effect and the second effect can be obtained without requiring modification of an existing application by incorporating the apparatus into an operating system. The reason is that a memory address space used by a general application is a virtual address virtualized by the MMU, and this device copies the contents of the memory in an overheated state to another memory, and then copies the physical address of the copy source. This is because the virtual address associated with is reassigned to the physical address of the copy destination, so that the address space observed from the application and its contents are not changed.

  In addition, the memory access processing system according to the present invention can be applied to a computer equipped with a large-capacity memory, in particular, for increasing the degree of integration of memory modules per cooling device.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 100 Memory access processing system 110 Memory module 120 Temperature sensor 130 Page movement determination apparatus 140 Page movement destination selection apparatus 150 Memory management unit 200 CPU
300 External storage device

Claims (10)

A memory access processing system for processing a memory access requested by a CPU,
Among the plurality of memory module pages, in order to move a memory module page that is in an overheated state to a page in a memory module that is not in an overheated state, the virtual address of the page of the memory module that is in an overheated state and the overheated state A memory access processing system comprising a memory management unit for replacing virtual addresses of pages of no memory modules. A page move destination selecting unit for selecting a page of the memory module to be moved to which the page of the memory module in an overheated state is to be moved;
The memory management unit is configured to move a page of a memory module that is in an overheated state to a page of a memory module that is not in an overheated state among a plurality of memory module pages. The memory access processing system according to claim 1, wherein the page of the memory module selected by the page movement destination selection unit is switched. A page movement determination unit for determining whether or not to move the page of the memory module in an overheated state;
When the page movement determination unit determines that the page of the memory module in the overheated state should be moved, the page movement destination selection unit moves the page of the memory module in the overheated state. The memory access processing system according to claim 2, wherein the page is selected. A temperature measuring unit for measuring the temperature of the memory module;
The memory according to claim 3, wherein the page movement determination unit determines that the page of the memory module should be moved when the temperature of the memory module measured by the temperature measurement unit exceeds a predetermined threshold. Access processing system. The memory management unit writes the page of the memory module in the overheated state when replacing the virtual address of the page of the memory module in the overheated state and the virtual address of the page of the memory module not in the overheated state. The memory access processing system according to claim 1, wherein the memory access processing system is prohibited. The memory management unit writes the virtual address of the page of the memory module in the overheated state and the virtual address of the page of the memory module not in the overheated state to the page of the memory module in the overheated state. 6. The memory access processing system according to claim 1, wherein the stored data is replicated to a page of the memory module that is not in an overheated state. 7. The memory access according to claim 5, wherein when there is a write request from the CPU for a page of the overheated memory module in which writing is prohibited, the memory management unit leaves the content of the write request in a log. Processing system. The memory access processing system according to claim 7, wherein the memory management unit scans the log when there is a read request from the CPU for a page of the overheated memory module in which writing is prohibited. A control method for controlling a memory access processing system for processing a memory access requested by a CPU,
Among the plurality of memory module pages, a virtual address of the high-temperature memory module page, a virtual address of the low-temperature memory module page, and a virtual address of the low-temperature memory module page to move the high-temperature memory module page to the low-temperature memory module page. A control method comprising a memory management stage for exchanging. A program for a memory access processing system for processing a memory access requested by a CPU, the memory access processing system comprising:
Among the plurality of memory module pages, a virtual address of the high-temperature memory module page, a virtual address of the low-temperature memory module page, and a virtual address of the low-temperature memory module page to move the high-temperature memory module page to the low-temperature memory module page. A program that functions as a memory management unit that replaces.

Images