Importance

Loading Importance Indicators...

Abstract

A portion of the global memory of a multiprocessing computer system is allocated to each node, called local memory space. Data from a remote node may be copies to local memory space of a node such that accesses to the data may be performed locally rather than globally. The copies data is referred to as a shadow page. The global address of the data is translated to a local physical address for the node to which the data is copied. To reduce the size of the translation tables for converting between global addresses and local physical addresses, the page to which shadow copies may be stored and which global addresses may be converted to local physical addresses may be restricted. Multiple page of local memory space may be allocated to one entry of a local physical address to global address (LPA2GA) table. When a page is allocated to store shadow pages, an entry in the LPA2GA table associated with that page is marked as unavailable. Accordingly, new translations may not be stored to that entry of the LPA2GA table and other pages associated with that entry may not be allocated to store shadow pages. In a similar manner, multiple pages of the global address space are mapped to an entry in a global address to local physical address(GA2LPA) translation table. When data corresponding to a page within the global address space is stored as a shadow page, the entry associated with the global address is marked as unavailable. Accordingly, other pages associated with that entry of the GA2LPA table may not be stored as shadow pages because the entry is not available. The local copy of the data is not stored and the node must access the data globally. To decrease the probability that an entry is not available for a page, the GA2LPA table may be implemented as a set associative table. To further increase the availability of entries in the GA2LPA table, a skewed-associative cache that implements an insertion algorithm that realigns the translations in the table to maximize the utilization of the available entries is implemented.

Loading the Abstract Image...

First Claim