US4224664A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for detecting when the activity of one process in relation to a common piece of information interferes with any other process in a multiprogramming/multiprocessing computer system
Assignee: Bull HN Information Systems Inc
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Filing: 1976-05-07
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Granted: 1980-09-23
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Expires: 1996-05-07
Abstract
Abstract A multiprogramming/multiprocessing computer system for executing a plurality of processes sharing common information in the form of records, pages or messages, employing an apparatus for avoiding an interference between two processes seeking access to elements of common information. The system operates to store in a first memory utilization data in table form identifying the processes which have accessed each individual element of common information. A second memory stores a matrix of precedence data representing the relative order in which processes must access the common information in accordance with a predetermined set of access rules. When a first process enters a request to access an element of common information, the system identifies from the utilization table any other process which, according to the access rules, must be given precedence to the common information over the first process. Thereafter, the system inspects the second memory and determines from the precedence data therein whether any inverse precedence relationships have been detected and, if so, rejects the access request entered by the first process and moves on to process the next access request.
Inventors
- 👤 Mario G. Trinchieri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:52
CPC Classifications
G; G06; G06F; G06F9/00; G06F9/06; G06F9/46; G06F9/52; G06F9/524
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
214 words
In a multiprogramming/multiprocessing computer system for executing a plurality of processes sharing common information in the form of records, pages or messages, apparatus for operating said system to avoid interferences between processes seeking access to said common information comprising: first memory means storing utilization data identifying processes which have accessed said information; second memory means storing precedence data representing the relative order in which said processes identified in said utilization data must access said information in accordance with a predetermined set of access rules; identification means coupled to said first memory means for sensing said stored utilization data in response to a request made by a first process to access said information, said identification means responding to said utilization data to generate a precedence indication identifying any second process which has precedence over said first process to said information in accordance with said access rules; and search means coupled to said second memory means and to said identification means for sensing said stored precedence data and for rejecting said access request made by said first process if said precedence data indicates that said first process has precedence to said information over any process identified by said precedence indication, whereby the possibility of an interference occurring between two processes relative to said information is prevented.
Claim 2
Dependent Claim
214 words
In a multiprogramming/multiprocessing computer system for executing a plurality of processes sharing common information in the form of records, pages or messages, apparatus for operating said system to avoid interferences between processes seeking access to said common information comprising: first memory means storing utilization data identifying processes which have accessed said information; second memory means storing precedence data representing the relative order in which said processes identified in said utilization data must access said information in accordance with a predetermined set of access rules; identification means coupled to said first memory means for sensing said stored utilization data in response to a request made by a first process to access said information, said identification means responding to said utilization data to generate a precedence indication identifying any second process which has precedence over said first process to said information in accordance with said access rules; and search means coupled to said second memory means and to said identification means for sensing said stored precedence data and for rejecting said access request made by said first process if said precedence data indicates that said first process has precedence to said information over any process identified by said precedence indication, whereby the possibility of an interference occurring between two processes relative to said information is prevented.
Claim 3
Dependent Claim
35 words
The apparatus set forth in claim 1 further comprising: means included in said search means for approving said access request if said second memory means does not contain precedence data pertaining to said first process.
Claim 4
Dependent Claim
42 words
The apparatus set forth in claim 1 further comprising: means included in said search means for approving said access request if said precedence data indicates that said processes identified by said precedence indication have precedence to said information over said first process.
Claim 5
Dependent Claim
63 words
The apparatus set forth in claim 1 further comprising: means included in said search means for approving said access request if there is precedence data in said second memory means pertaining to said first process and said precedence data indicates that said first process has precedence to said information only with respect to processes other than the processes identified by said precedence indication.
Claim 6
Dependent Claim
49 words
The apparatus set forth in claim 2 further comprising: means responsive to said search means for storing in said second memory means, if said access request is approved, additional precedence data indicating that each process identified by said precedence indication has precedence to said information over said first process.
Claim 7
Dependent Claim
185 words
The apparatus set forth in claim 4 wherein said precedence data pertaining to said first process is stored in said memory means in the form of a series of recorded access digits grouped in an area of said second memory means associated with said first process, each said recorded access digit representing a condition of precedence or non-precedence of said first process with respect to another process, the identity of said other process being represented by the location within said area occupied by said respective digit, and wherein said search means comprises: means for sequentially sensing the access digits in said second memory means area pertaining to said first process; means coupled to said sensing means for determining for each access digit sensed whether said digit represents a condition of precedence or non-precedence and, for each precedence digit, whether its location within said area associates it with a process identified by said precedence indication; and means responsive to said determining means for rejecting said access request if said determining means determines that a precedence digit is associated with a process identified by said precedence indication.
Claim 8
Dependent Claim
105 words
The apparatus set forth in claim 6 wherein: said sensing means further operates to sequentially sense the access digits in the areas of said second memory means associated with each additional process, other than the processes identified by said precedence indication, for which a precedence digit is detected in said area pertaining to said first process; and said determining means further operates to determine for each access digit read for said additional processes whether said digit represents a condition of precedence or non-precedence and, for each precedence digit, whether its location within its respective area associates it with a process identified by said precedence indication.
Claim 9
Dependent Claim
30 words
The apparatus set forth in claim 7 further comprising: means for approving said access request if no precedence digit read is associated with a process identified by said precedence indication.
Claim 10
Dependent Claim
49 words
The apparatus set forth in claim 8 further comprising: means responsive to said search means for storing in said second memory means, if said access request is approved, additional precedence data indicating that each process identified by said precedence indication has precedence to said information over said first process.
Claim 11
Dependent Claim
49 words
The apparatus set forth in claim 4 further comprising: means responsive to said search means for storing in said second memory means, if said access request is approved, additional precedence data indicating that each process identified by said precedence indication has precedence to said information over said first process.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-09-23 | 1984-03-24 | 1984-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-23 | 1988-03-24 | 1988-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-23 | 1992-03-24 | 1992-09-23 | $7700.00 | Window Closed / Lapsed |