Controlling the state of duplexing of coupling facility structures

• US 9,860,315 B2
• Filed: 02/02/2017
• Issued: 01/02/2018
• Est. Priority Date: 09/10/1998
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Elko, David A., Goss, Steven N., Jordan, Michael J., Kurdt, Georgette L., Nick, Jeffrey M., Pushong, Kelly B., Surman, David H.
• Primary Examiner(s): NGUYEN, MERILYN P
• Application Number:
  US15/422,561
• Publication Number:
  US 20170149889A1
• Time in Patent Office: 334 Days
• CPC Class Codes: G06F 11/2007 using redundant communication media
• CPC Class Codes: G06F 11/2028 eliminating a faulty processor or activating a spare
• CPC Class Codes: G06F 11/2097 maintaining the standby controller/processing unit updated initialisation or re-synchronisation thereof G06F11/1658 and subgroups
• CPC Class Codes: H04B 1/74 for increasing reliability, e.g. using redundant or spare channels or apparatus replacing by standby devices for amplifiers H03F1/52, H03F1/542
• CPC Class Codes: H04L 1/22 using redundant apparatus to increase reliability
• CPC Class Codes: H04L 41/50 Network service management, e.g. ensuring proper service fulfilment according to agreements
• CPC Class Codes: H04L 43/08 Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 67/108 characterised by resources being split in blocks or fragments
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database

Abstract

A coupling facility is coupled to one or more other coupling facilities via one or more peer links. The coupling of the facilities enables various functions to be supported, including the duplexing of structures of the coupling facilities. Duplexing is performed on a structure basis, and thus, a coupling facility may include duplexed structures, as well as non-duplexed or simplexed structures.

Claims

1. A computer-implemented method of managing state of coupling facility structures, said computer-implemented method comprising:

obtaining, by a processor, a control data structure used to provide state of at least one structure of a coupling facility, the state relating to duplexing of the at least one structure, wherein state of a structure of the at least one structure reflects whether the structure is duplexed in that a plurality of instances of the structure are concurrently updated;

obtaining from the control data structure the state of the structure; and

detecting, by the processor based on the obtained state of the structure, a change in the state of the structure and taking action based thereon, wherein the taking action includes splitting a command into a plurality of commands and sending the plurality of commands to the plurality of instances of the structure, based on detecting that the change in state is from duplexing not active to duplexing active, and suspending duplexed commands for the structure, based on detecting the change in state is from duplexing active to duplexing not active.

2. The computer-implemented method of claim 1, wherein the control data structure comprises at least one indicator for the at least one structure.

3. The computer-implemented method of claim 2, further comprising setting an indicator of the structure of the at least one structure to activate duplexing of the structure.

4. The computer-implemented method of claim 3, further comprising:

determining whether a remote coupling facility is connected to the coupling facility; and

setting the indicator, based on a determination that the remote coupling facility is connected.

5. The computer-implemented method of claim 3, further comprising resetting the indicator to deactivate duplexing.

6. The computer-implemented method of claim 5, wherein the resetting causes a duplexed command issued after duplexing is deactivated to be suspended.

7. The computer-implemented method of claim 6, further comprising detecting, by one or more systems coupled to the coupling facility, a suspended state of the duplexed command.

8. The computer-implemented method of claim 7, wherein the detecting is independent of a message exchange.

9. The computer-implemented method of claim 2, wherein the at least one indicator is located in a vector, the vector indexed by a structure identifier.

10. The computer-implemented method of claim 1, wherein the state of the structure of the at least one structure is used to control execution of one or more commands associated with the structure.