80 results about "Virtual memory management" patented technology

An apparatus, system, and method for application direct virtual memory management. The method includes detecting a system memory access to a virtual memory address within a monitored page of data not loaded in main memory of a computing system. The method includes determining a first swap address for a loaded page of data in the main memory. The first swap address is defined in a sparse virtual address space exposed by a persistent storage device. The first swap address is associated in an index with a first deterministic storage location. The index is managed by the persistent storage device. The method includes storing the loaded page on a persistent storage device at the first deterministic storage location. The method includes moving the monitored page from a second deterministic storage location to the main memory. The second deterministic storage location is associated with a second swap address in the index.

The invention is used in a virtual machine monitor for a multiprocessing system that includes a virtual memory system. During a software-based processing of a guest instruction, including translating or interpreting a guest instruction, mappings between virtual addresses and physical addresses are retained in memory until processing of the guest instruction is completed. The retained mappings may be cleared after each guest instruction has been processed, or after multiple guest instructions have been processed. Information may also be stored to indicate that an attempt to map a virtual address to a physical address was not successful. The invention may be extended beyond virtual machine monitors to other systems involving the software-based processing of instructions, and beyond multiprocessing systems to other systems involving concurrent access to virtual memory management data.

A method and an apparatus that improves virtual memory management. The proposed method and apparatus provides an application with an efficient channel for communicating information about future behavior of an application with respect to the use of memory and other resources to the OS, a paging daemon, and other system software. The state of hint bits, which are integrated into page table entries and TLB entries and are used for communicating information to the OS, can be changed explicitly with a special instruction or implicitly as a result of referencing the associated page. The latter is useful for canceling hints. The method and apparatus enables memory allocators, garbage collectors, and compilers (such as those used by the Java platform) to use a page-aligned heap and a page-aligned stack to assist the OS in effective management of memory resources. This mechanism can also be used in other system software.

A gigabit Ethernet adapter provides a provides a low-cost, low-power, easily manufacturable, small form-factor network access module which has a low memory demand and provides a highly efficient protocol decode. The invention comprises a hardware-integrated system that both decodes multiple network protocols byte-streaming manner concurrently and processes packet data in one pass, thereby reducing system memory and form factor requirements, while also eliminating software CPU overhead. A preferred embodiment of the invention comprises a plurality of protocol state machines that decode network protocols such as TCP, IP, User Datagram Protocol (UDP), PPP, Raw Socket, RARP, ICMP, IGMP, iSCSI, RDMA, and FCIP concurrently as each byte is received. Each protocol handler parses, interprets, and strips header information immediately from the packet, requiring no intermediate memory. The invention provides an internet tuner core, peripherals, and external interfaces. A network stack processes, generates and receives network packets. An internal programmable processor controls the network stack and handles any other types of ICMP packets, IGMP packets, or packets corresponding to other protocols not supported directly by dedicated hardware. A virtual memory manager is implemented in optimized, hardwired logic. The virtual memory manager allows the use of a virtual number of network connections which is limited only by the amount of internal and external memory available.

Systems and methods for program directed memory access patterns including a memory system with a memory, a memory controller and a virtual memory management system. The memory includes a plurality of memory devices organized into one or more physical groups accessible via associated busses for transferring data and control information. The memory controller receives and responds to memory access requests that contain application access information to control access pattern and data organization within the memory. Responding to memory access request includes accessing one or more memory devices. The virtual memory management system includes: a plurality of page table entries for mapping virtual memory addresses to real addresses in the memory; a hint state responsive to application access information for indicating how real memory for associated pages is to be physically organized within the memory; and a means for conveying the hint state to the memory controller.

The present invention proposes effective solutions for the design of Virtual Memory Management for applications with dynamic data types in an embedded (HW or SW) processor context. A structured search space for VMM mechanisms with orthogonal decision trees is presented. Based on said representation a systematic power exploration methodology is proposed that takes into account characteristics of the applications to prune the search space and guide the choices of a VMM for data dominated applications. A parameterizable model, called Flexible Pools, is proposed. This model limits the exploration of the Virtual Memory organization considerably without limiting the optimization possibilities.

A fault tolerant synchronized virtual memory manager for use in a load sharing environment manages memory allocation, memory mapping, and memory sharing in a first processor, while maintaining synchronization of the memory space of the first processor with the memory space of at least one partner processor. In one embodiment, synchronization is maintained via paging synchronization messages such as a space request message, an allocate memory message, a release memory message, a lock request message, a read header message, a write page message, a sense request message, an allocate read message, an allocate write message, and / or a release pointer message. Paging synchronization facilitates recovery operations without the cost and overhead of prior art fault tolerant systems.

A virtual memory management unit (306) includes a redundancy insertion module (307) which is used for inserting redundancy into an encoded data stream to be compressed, such that after being compressed each logical data block fits into a different one from a set of equal-sized physical data blocks of a given size. For example, said redundancy may be given by no-operation (NOP) instructions represented by a number of dummy sequences of a given length (L) into an encoded data stream to be compressed, each dummy sequence being composed of a number of identical binary or hexadecimal fill-in values.

An interface is provided between a virtual cluster proxy and a virtual I / O server on a logical partitioned platform. The virtual I / O server is configured to support virtual real memory. A command is received from a virtual cluster proxy. The virtual cluster proxy identifies whether the command is a virtual real memory command or a virtualization command. Virtual real memory commands and virtualization commands are marked by the virtual cluster proxy with a virtualization marker. The virtualization marker indicates that the command is a virtual real memory command or a virtualization command. The command is then forwarded to a logical partitioned platform. A virtual memory manager intercepts the command and identifies whether the command has been marked with the virtualization marker. If the command is marked with the virtualization marker, the virtual memory manager reroutes the command to the virtual I / O server.

A CPU 5 is provided with both the functionality of issuing an external bus access request directly to an external memory interface 3 and the functionality of issuing a DMA transfer request to a DMAC 4. Accordingly, in the case where data is randomly accessed at discrete addresses, an external bus access request is issued directly to the external memory interface 3, and in the case of data block transfer or page swapping as requested by a virtual memory management unit or the like, a DMA transfer request is issued to the DMAC 4, so that it is possible to effectively access the external memory 50.

A method for calculating a block cache size for a host process or application on a computer based at least upon virtual memory page evictions and / or virtual memory page reclamations for the computer. A virtual memory page eviction is the act of removing the contents of a physical memory page for the purpose of loading it with the contents of another virtual memory page. A virtual memory page reclamation is the return of a page to a working set that was previously removed by the operating system due to memory constraints. The page must not have been evicted. Additional fundamental properties of the application and the computer may be used, such as available physical memory on the computer, total physical memory, and block evictions. A block eviction is the act of removing the contents of a block from the block cache for the purpose of loading it with new contents.

A virtual memory management apparatus and method to execute virtual machines in a multi-processor and multi-memory environment are provided. The virtual memory management apparatus includes a virtual system memory manager configured to allocate a virtual system memory to a virtual machine. The virtual memory management apparatus further includes a virtual swap device map storage configured to store location information of virtual swap devices that are able to be allocated to the virtual machine. The virtual memory management apparatus further includes a virtual swap device manager configured to allocate a virtual swap device to the virtual machine with reference to a virtual swap device map.

Operating system virtual memory management for hardware transactional memory. A method may be performed in a computing environment where an application running on a first hardware thread has been in a hardware transaction, with transactional memory hardware state in cache entries correlated by memory hardware when data is read from or written to data cache entries. The data cache entries are correlated to physical addresses in a first physical page mapped from a first virtual page in a virtual memory page table. The method includes an operating system deciding to unmap the first virtual page. As a result, the operating system removes the mapping of the first virtual page to the first physical page from the virtual memory page table. As a result, the operating system performs an action to discard transactional memory hardware state for at least the first physical page. Embodiments may further suspend hardware transactions in kernel mode. Embodiments may further perform soft page fault handling without aborting a hardware transaction, resuming the hardware transaction upon return to user mode, and even successfully committing the hardware transaction.

A method of implementing virtualization involves an improved approach to virtual memory management. An operating system includes a kernel, a resource control framework, a virtual memory subsystem, and a virtualization subsystem. The virtualization subsystem is capable of creating separate environments that logically isolate applications from each other. The virtual memory subsystem utilizes swap space to manage a backing store for anonymous memory. The separate environments share physical resources including swap space. When a separate environment is configured, properties are defined. Configuring a separate environment may include specifying a swap cap that specifies a maximum amount of swap space usable by the separate environment. The resource control framework includes a swap cap resource control. The swap cap resource control is enforced by the kernel such that during operation of the separate environment, the kernel enforces the swap cap specified when the separate environment was configured.

A computer system using virtual memory provides hybrid memory access either through a conventional translation between virtual memory and physical memory using a page table possibly with a translation lookaside buffer, or a high-speed translation using a fixed offset value between virtual memory and physical memory. Selection between these modes of access may be encoded into the address space of virtual memory eliminating the need for a separate tagging operation of specific memory addresses.

Systems and methods for program directed memory access patterns including a memory system with a memory, a memory controller and a virtual memory management system. The memory includes a plurality of memory devices organized into one or more physical groups accessible via associated busses for transferring data and control information. The memory controller receives and responds to memory access requests that contain application access information to control access pattern and data organization within the memory. Responding to memory access request includes accessing one or more memory devices. The virtual memory management system includes: a plurality of page table entries for mapping virtual memory addresses to real addresses in the memory; a hint state responsive to application access information for indicating how real memory for associated pages is to be physically organized within the memory; and a means for conveying the hint state to the memory controller.

Operating system virtual memory management for hardware transactional memory. A system includes an operating system deciding to unmap a first virtual page. As a result, the operating system removes the mapping of the first virtual page to the first physical page from the virtual memory page table. As a result, the operating system performs an action to discard transactional memory hardware state for at least the first physical page. Embodiments may further suspend hardware transactions in kernel mode. Embodiments may further perform soft page fault handling without aborting a hardware transaction, resuming the hardware transaction upon return to user mode, and even successfully committing the hardware transaction.

A virtual mode virtual memory manager method and apparatus are provided. Mechanisms are provided for allowing a virtual memory manager to operate in virtual mode utilizing virtual addresses for all of its own data structures, allowing for physical discontinuity of the physical memory backing those data structures. First order virtual memory manager metadata is included for resolving system wide virtual memory page faults. Second order virtual memory manager metadata is provided to resolve faults on the first order virtual memory manager metadata. The second order virtual memory manager metadata is associated with pinned entries in a page table and thus, faults on the second order virtual memory manager metadata cannot occur.

The present invention is directed to a loadable virtual memory manager, and generally to a computer operating system capable of supporting application programs running in a computer having a working memory, the computer operating system including a kernel resident in the working memory at run time, and a loadable virtual memory manager resident at link time outside of the working memory and dynamically loadable into the working memory at run time upon demand of one of the application programs. The kernel includes a loader for loading the virtual memory manager into the working memory in response to a demand from one of the application programs. The computer is able to access a storage memory separate from the working memory, the loadable virtual memory manager residing at link time in the storage memory. The loader loads the virtual memory manager from the storage memory to the working memory. The loadable virtual memory manager is removable from the working memory upon lack of demand therefor by the application programs.

The invention discloses a virtual memory management method and a virtual memory management device for mass data processing, belongs to the technical field of computer system optimization and is mainly applied to one-step real-time processing of computer mass data in quantity higher than that of available physical memory. When memory allocation reaches an assigned critical value, the most suitable physical memory is found to substitute for disc virtual memory according to memory block access correlation composite index and memory allocation application size. By a memory allocation method based on size matching, a front segment of an allocation unit is allocated to an object having high requirement for memory while a rear segment is allocated to an object having low requirement for memory; thus transform matching degree of the virtual memory is increased while data movement amount is reduced. By the virtual memory management method, during allocation of mass memories which are of capacity ranging from 100KB to 10MB and of the total quantity higher than the available physical memory, Thrashing in scheduling of the virtual memory is decreased, scheduling is accurate and predictable to some degree, and system performance is improved remarkably.

The invention discloses a server performance testing method and system applied to a server with a Linux system. The method comprises the steps that all performance parameters influencing the stability and reliability of the server are tested, wherein the performance parameters comprise an Linux system kernel performance parameter, a CPU performance parameter, a memory performance parameter, a network performance parameter, an interrupt system call performance parameter, a virtual file system performance parameter, a dynamic file system performance parameter, a logic volume management performance parameter, a process scheduling performance parameter, a virtual memory management performance parameter and / or an input and output performance parameter; the performance parameters are comprehensively analyzed, and the testing result of the whole performance of the server is obtained. The comprehensive performance of the server can be tested and evaluated more objectively, truly and accurately.

The invention discloses a management method of a virtual memory of a computer. The method comprises the following steps: identifying a use frequency and use time of an application in the computer after conforming that the virtual memory is established successfully through monitoring and identification of the application in the computer, comparing data of the use frequency and the use time of the application with standard data preset in a computer system, judging a comparison result, classifying application operating data into a hidden region and an operating region in the virtual memory of a solid-state hard disk, and controlling the virtual memory of the solid-state hard disk to be started or stopped by ending the operation of the application in the computer by judging whether the number of the applications in the hidden region reaches a preset range value or not. According to the management method disclosed by the invention, the operating number of the applications can be increased, and the management efficiency of the virtual memory is improved; meanwhile, the memory use and distribution efficiency of the applications is substantially improved, so that the working efficiency of the computer is improved.

Methods, computer-readable media, and systems for virtual memory management in Java™ are provided. In some illustrative embodiments, a computer-readable medium storing a Java program that, when executed by a processor, performs a method for virtual memory management is provided. The method includes creating a Java representation of a page table, wherein each entry of the Java representation comprises a Java representation of a page descriptor, changing a field of a Java representation of a page descriptor in the Java representation of the page table, and updating a corresponding field in a page descriptor of a system level page table using the contents of the field in the Java representation of the page descriptor. Some illustrative embodiments provide a computer-readable medium storing a Java program that, when executed by a processor, performs a method for virtual memory management that includes creating a Java representation of a segment descriptor, changing a field of the Java representation of the segment descriptor, and updating a corresponding field in a system level segment descriptor using the contents of the field in the Java representation of the segment descriptor.