A dynamic memory is disclosed, in which data is rearranged among its internal memory locations in accordance with either of two different shuffle operations. The shuffle operations, an In Shuffle and an Out Shuffle, rearrange the data in a manner similar to the manner in which cards of a deck are rearranged when shuffled. Using only the two shuffle operations, a method of random accessing data in the theoretical minimum time is disclosed, for all odd-sized memories and all memories of size 2.sup...

In a multiple-block-per-entry buffer memory (BS) of the swap or store-in type, a swap-out buffer (SOB) having a capacity for at least a block is provided. On the occasion of replacing, a memory access sequence control responds to change bits and validity bits associated with an entry to be replaced as well as the block address designated for memory access so as to execute the data transfer from a main memory (MS) to BS in preference to the sweeping-out of data from BS to SOB so long as the block...

A plurality of external storage devices for storing therein data processing history information. The history information obtained from the processing executed in a data processing system is cyclically written in principle in these external storage devices each time the history information occurs, thereby distributing the load required for the processing to store the history information.

A storage arrangement is used as an associative memory having a main memory serving to accommodate the data composed of an associative component (association word) and a non-associative component. A comparator device serves to compare the associative part of the read-out data with a search word and address converters serve to derive storage addresses from the association word or the search word or from parts of such words (prefix). An extension counter is provided whose count influences the addr...

A virtual memory management system and method in which the mechanism for swapping in pages of memory in secondary storage replaces the overhead of retrieving pages from secondary storage by swapping logically contiguous clusters of pages each time that a page from secondary memory is needed. To improve the efficiency of in-page clustering, the size of the clusters which are read in are heuristically adjusted. Clustered pages are not entered into the working set until they are accessed by the pro...

A cache location selector selects locations in a cache for loading new information using either a valid chain, if not all locations already contain valid information, or a history loop otherwise. The valid chain selects the "highest" location in the cache which does not already contain valid information. The history loop selects locations in accordance with a modified form of the First-In-Not-Used-First-Out (FINUFO) replacement scheme. Both the valid chain and the history loop are fully and effi...

A process for partially swapping real storage areas used by a program is utilized in a computer system which executes programs by multiprogramming under control of a virtual storage type operating system. A first portion of a real storage area, allocated to a program to be swapped out, remains allocated to that program while the contents of a second portion of the real storage area are saved in an auxiliary storage so that the second portion is deallocated from that program. The saved contents o...

A computer system wherein a paging technique is used to expand the usable non-volatile memory capacity beyond a fixed address space limitation. The computer system of the preferred embodiment includes a flash memory component for storing non-volatile code and data including a system BIOS in the upper 128K of memory. The useful BIOS memory space is effectively increased while maintaining the address boundary of the upper 128K region. The address space of the non-volatile memory device is logicall...

A method and process for providing a memory dump of less than the entire contents of memory is provided. The memory locations to be dumped are selected on the basis of recency of use, so that there is a high probability that portions of memory needed for analysis or evaluation of the computer system will be included in the selective dump. Preferably, the select ion is made on the basis of information or hardware which is already provided in the computer system. In one preferred embodiment, memor...

A queue structure is functionally equivalent to individual FIFO bank queues but requires only slightly more hardware than the single BSM queue approach. The queue structure uses "self-advancing" WAITING queues (one per BSM) in which there is a one-to-one correspondence between a (valid) queue position and a busy bank within a given BSM. However, the position/bank relationship is dynamically managed such that positions only exist for busy banks, thereby essentially providing a FIFO queue per bank...