Eugene W Johnson

US Patent:

58527478, Dec 22, 1998

Filed:

Sep 8, 1995

Appl. No.:

8/525991

Inventors:

Robert Bradley Bennett - Endwell NY
Eugene Johnson - Vestal NY
Terrence L. Woodnorth - Endicott NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1314

US Classification:

395860

Abstract:

A client/server computer system manages shared files. A client includes a data cache and an associated cache manager, and executes a client application that requests data from a shared file. In response to the request, the client cache manager determines if the data is currently stored in the data cache, and if so, grants the client access to the data in the cache. However, if the data is not currently stored in the cache, the client cache manager sends to the server a request for multiple consecutive blocks of data beginning with the first block containing the data requested by the client from the shared file. The server includes a token manager which receives the request, and in response (a) awards the token for a first data block specified in the request regardless of contention for the first data block and (b) awards tokens for all other consecutive blocks following the first block of the multiple blocks held by a client who also holds the token for the first block. However, if another client currently holds a contending token for one of the consecutive blocks other than the first block but does not also hold the token for the first block, then the token management process awards only the tokens for the first block and all blocks between the first block and the one block.

US Patent:

57616787, Jun 2, 1998

Filed:

Jun 26, 1996

Appl. No.:

8/670883

Inventors:

Edward Joseph Bendert - Vestal NY
Robert Bradley Bennett - Endwell NY
Eugene Johnson - Austin TX
Robert Michael Nugent - Nichols NY
James Michael Showalter - Endicott NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1740

US Classification:

707204

Abstract:

A system and method efficiently manage clones of an object group. A base storage area contains metadata for each of multiple objects in the object group. The metadata for each object identifies data within each object. The system receives a request to clone a base storage area, and in response, the system creates a clone storage area containing an identification of the base storage area but not the metadata. If there is a subsequent request to update a portion of one of the objects, then the system copies the portion, copies the metadata into the clone storage area for the one object, makes the update to the object copy and changes the metadata in the base storage area to identify the portion copy instead of the original portion. If there is no subsequent request to update any of the multiplicity of objects, then the system does not copy the metadata for any of the multiplicity of objects into the clone storage area.

US Patent:

62758675, Aug 14, 2001

Filed:

Sep 12, 1995

Appl. No.:

8/527148

Inventors:

Edward Joseph Bendert - Vestal NY
Robert Bradley Bennett - Endwell NY
Eugene Johnson - Vestal NY
Robert Micheal Nugent - Nichols NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 954

US Classification:

709316

Abstract:

Selected server operations that affect objects in a distributed computing system can be off-loaded from servers at which the objects are stored to other servers without the requirement of vertical partitioning of the affected objects and without off-loading entire affected objects. A client environment process that requests an operation on an object is notified of a task server to which selected off-load operations should be sent. The client preferably stores the task server identifier and thereafter sends such operation request directly to the identified task server. The object metadata information can be stored in the client environment, if desired. The object metadata at the owning repository server is maintained, if affected by the requested operation. A single task server can perform off-loaded functions from several other repository servers at the same node and at other nodes, and in that way reduce the workload of many servers. The functions that can be off-loaded include named pipe functions and byte range file lock operations.

US Patent:

59567120, Sep 21, 1999

Filed:

Jun 7, 1995

Appl. No.:

8/472153

Inventors:

Robert Bradley Bennett - Endwell NY
Brian Paul Dixon - Newark Valley NY
Eugene Johnson - Vestal NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1730

US Classification:

707 8

Abstract:

A client-server distributed computer processing system provides staged byte range locking with three levels of lock complexity and contention. When locking activity for a data object involves a plurality of clients, locking is managed centrally in the server operating environment. When only a single client is involved in requesting a lock on a data object such as a data file or portion of a data file, the requesting client can be permitted to manage the locking locally in the requesting client operating environment. Client-managed locking involves two stages of locking complexity on an object-by-object basis. The first stage of client locking involves only a log of current lock activity and handles relatively simple locking. When locking becomes more complex, the client locking is migrated to a second local locking stage, where more complex data structures can support lock fragmentations that affect various portions of the data object, such as partially overlapped byte ranges. Migration between the three stages of locking uses a high level interface rather than migrating implementation-dependant structures and thereby avoids implementation dependencies and local optimization restrictions.

US Patent:

56689586, Sep 16, 1997

Filed:

Sep 12, 1995

Appl. No.:

8/526937

Inventors:

Edward Joseph Bendert - Vestal NY
Robert Bradley Bennett - Endwell NY
Eve Suzanne Berman - Binghamton NY
Susan Marie Farrell - Vestal NY
Eugene Johnson - Vestal NY
Robert Michael Nugent - Nichols NY
Mary Ellen Vendryes - Newark Valley NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1730

US Classification:

395308

Abstract:

A computer system manages first and second different file systems. The system comprises first and second, different file managers having first and second different APIs for the first and second file systems, respectively. The system also comprises a hybrid file manager for managing the second file system based on requests made using the first API. The hybrid manager applies rules from both APIs to control atomicity of requests, access concurrency, and data consistency rules. The hybrid rules prevent violation of the rules of either API.