Method for identifying a system holding a `Reserve`

Details Method for identifying a system holding a `Reserve` Method for identifying a system holding a `Reserve`

1992-09-22

1995-11-28

Beausoliel, Jr., Robert W.

395650, 39518208, G06F 1134

Patent

active

054716098

ABSTRACT:
A method and accompanying apparatus for identifying a system, such as illustratively a central processing unit (CPU), that holds a "reserve" for a shared physical device (480, 482, 484) employed within illustratively a multi-processing environment. Specifically, sense data (500) returned by execution of a Reset Allegiance (R/A) command, by a control unit of a shared device, contains the path group identifier (PGID) (300) for a path group (680) through which a reserve has been extended. Inasmuch as the PGID is created in an identical manner for all operating systems (VM or MVS) that share devices through an MVS operating system (600), the PGID advantageously and uniquely specifies the CPU then holding this reserve. The PGID contained in the returned sense data is then translated, through a table look-up operation, in illustratively a so-called IOS Record (1100) situated in a Coupled Dataset (620) for a sysplex installation (455), to yield a common system name of the particular CPU then holding the reserve.

REFERENCES:
patent: 4152764 (1979-05-01), Connors et al.
patent: 4207609 (1980-06-01), Luiz et al.
patent: 4455605 (1984-06-01), Cormier et al.
patent: 4472771 (1984-09-01), Bienvenu et al.
patent: 4674033 (1987-06-01), Miller
"Alternate Path Group ID Support", Disclosure No. 31964 Research Disclosure, Nov. 1990 (copyright Kenneth Mason Publications Ltd., England).
J. C. O'Quin et al., "Takeover Scheme for Control of Shared Disks", IBM Technical Disclosure Bulletin, vol. 32, No. 2, Jun. 1989, pp. 378-380.
Principles of Operation--IBM System/370 Extended Architecture, IBM Publication SA22-7085-1, Second Edition, Jan. 1987, (copyright 1987, International Business Machines Corp.), pp. 13-1 through 13-9.
D. W. Burt et al., "Contingent Allegiance Enhanced Detection and Reset Function", IBM Technical Disclosure Bulletin, vol. 26, No. 3B, Aug. 1983, pp. 1624-1625.
A. S. Merritt, "Testing of Device Reservation State", IBM Technical Bulletin, vol. 24, No. 11A, Apr. 1982, pp. 5749-5750.

Affiliated with

Also associated with

Rating

Method for identifying a system holding a `Reserve` does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for identifying a system holding a `Reserve`, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for identifying a system holding a `Reserve` will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2020649