
US Patent No: 5,379,391
Number of patents in Portfolio can not be more than 2000
Method and apparatus to access data records in a cache memory by multiple virtual addresses
Stats
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Jan 3, 1995
Issued date -
Mar 1, 1991
filing date -
07/663,099
serial no -
In Force
status
Importance
Abstract
The data record copy apparatus for a virtual memory system instantaneously makes a copy of a selected data record by simply generating a new set of pointers to reference the same physical memory location as the original reference pointer. All the pointers referencing the same physical memory space are stored in the virtual memory mapping tables to record all the virtual addresses of the data record. When the original data record is staged to an associated cache memory or a copy of the data record is in cache memory, the consistency of the data record is maintained by loading all the virtual addresses of the data record from the mapping tables to the hash table and collision list of the cache memory. Thus, any access of one of these virtual addresses will result in the virtual memory system locating the single data record instance in cache memory. If an associated host processor attempts to update the data record at one of these virtual addresses, the virtual memory system copies the data record to a new cache memory location so that a unique instance of the data record is available for update while the remaining virtual addresses still point to the original data record in cache memory.
First Claim
Related Publications
International Classification(s)
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Cited Art
| Patent Info | (Count) | # Cites | Year |
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