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Abstract: Nested paging is a hardware solution for alleviating the software memory management overhead imposed by system virtualization. Nested paging complements existing page walk hardware to form a two-dimensional (2D) page walk, which reduces the need for hypervisor intervention in guest page table management. However, the extra dimension also increases the maximum number of architecturally-required page table references.This paper presents an in-depth examination of the 2D page table walk overhead and options for decreasing it. These options include using the AMD Opteron processor's page walk cache to exploit the strong reuse of page entry references. For a mix of server and SPEC benchmarks, the presented results show a 15%-38% improvement in guest performance by extending the existing page walk cache to also store the nested dimension of the 2D page walk. Caching nested page table translations and skipping multiple page entry references produce an additional 3%-7% improvement.Much of the remaining 2D page walk overhead is due to low-locality nested page entry references, which result in additional memory hierarchy misses. By using large pages, the hypervisor can eliminate many of these long-latency accesses and further improve the guest performance by 3%-22%.

Abstract: A non-volatile memory system ( 3 ) is proposed consisting of a first non-volatile flash memory ( 5 ) having a plurality of blocks, each block having a plurality of pages, each block being erasable and each page being programmable, and a second non-volatile random access memory ( 23 ) having a plurality of randomly accessible bytes. The second non-volatile memory ( 23 ) stores data for mapping logical blocks to physical blocks and status information of logical blocks. Each logical block has an associated physical page pointer stored in the second non-volatile memory ( 23 ) that identifies the next free physical page of the mapped physical block to be written. The page pointer is incremented after every page write to the physical block, allowing all physical pages to be fully utilized for page writes. Furthermore, a method of writing and reading data is disclosed whereby the most recently written physical page associated with a logical address is identifiable by the memory system without programming flags into superseded pages, or recording time stamp values in any physical page or block of the first non-volatile memory ( 5 ). Furthermore, a method is provided for a logical block to be mapped to two physical blocks instead of one to provide additional space for page writes, resulting in reduction in page copy operations, thereby increasing the performance of the system.

Abstract: Systems and/or methods that facilitate a search of a memory component(s) to locate a desired logical block address (LBA) associated with a memory location in a memory component are presented. Searches to locate a desired LBA(s) in a memory component(s) associated with a processor component are offloaded and controlled by the memory component(s). A search component searches pages in the memory array to facilitate locating a page of data associated with an LBA stored in the memory component. The search component can retrieve a portion of a page of data in a block in the memory component to facilitate determining whether the page contains an LBA associated with a command based in part on command information. The search component can search pages in the memory component until a desired page is located or a predetermined number of searches is performed without locating the desired page.

Abstract: In a first embodiment of the present invention, a method for caching in a processor system having virtual memory is provided, the method comprising: monitoring slow memory in the processor system to determine frequently accessed pages; for a frequently accessed page in slow memory: copy the frequently accessed page from slow memory to a location in fast memory; and update virtual address page tables to reflect the location of the frequently accessed page in fast memory.