Leasing for failure detection

• US 20010000812A1
• Filed: 12/20/2000
• Published: 05/03/2001
• Est. Priority Date: 10/11/1996
• Status: Active Grant

• Current Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Waldo, James H., Wollrath, Ann M., Arnold, Kenneth C.R.C., Scheifler, Robert
• Granted Patent: US 6,760,736 B2
• Time in Patent Office: Days
• US Class Current: 709/225
• CPC Class Codes: G06F 12/023 Free address space management
• CPC Class Codes: G06F 12/0253 Garbage collection, i.e. reclamation of unreferenced memory
• CPC Class Codes: G06F 12/0261 using reference counting
• CPC Class Codes: G06F 16/289 Object oriented databases
• CPC Class Codes: G06F 9/4411 Configuring for operating with peripheral devices; Loading of device drivers
• CPC Class Codes: G06F 9/465 Distributed object oriented systems remote method invocation [RMI] G06F9/548
• CPC Class Codes: G06F 9/5011 the resources being hardware resources other than CPUs, Servers and Terminals
• CPC Class Codes: G06F 9/5016 the resource being the memory
• CPC Class Codes: G06F 9/5022 Mechanisms to release resources
• CPC Class Codes: G06F 9/5055 considering software capabilities, i.e. software resources associated or available to the machine
• CPC Class Codes: G06F 9/5061 Partitioning or combining of resources
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: G06F 9/547 Remote procedure calls [RPC]; Web services
• CPC Class Codes: H04L 12/417 with deterministic access, e.g. token passing
• CPC Class Codes: H04L 12/433 with asynchronous transmission, e.g. token ring, register insertion
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users
• CPC Class Codes: Y10S 707/99953 : Recoverability
• CPC Class Codes: Y10S 707/99957 : Garbage collection

Abstract

A system for using a lease to detect a failure and to perform tailure recovery is provided in using this system, a client requests a lease from a server to utilize a resource managed by the server for a period of time. Responsive to the request, the server grants the lease, and the client continually requests renewal of the lease. If the client fails to renew the lease, the server detects that an error has occurred to the client. Similarly, if the server fails to respond to a renew request, the client detects that an error has occurred to the server. As part of the lease establishment, the client and server exchange failure-recovery routines that each invokes if the other experiences a failure.

Claims

1. A method in a data processing system having a client and a server, comprising the steps of:

requesting a lease by the client from the server to use a resource managed by the server, the lease request containing a first recovery routine;

granting the lease by the server so that the client can utilize the resource tor a period of time and sending a second recovery routine to the client;

utilizing the resource by the client;

determining by the client when the period of time is near expiration;

sending a request to the server to renew the lease when the client determines that the lease is near expiration;

determining whether the renew request is successful;

invoking the second recovery routine by the client to perform failure recovery for the server when the client determines that the renew request is unsuccessful;

determining by the server when the lease has expired;

invoking the first recovery routine by the server when the lease has expired to perform failure recovery for the client.

2. A failure detection method for a distributed system, comprising the steps, performed by a processor, of:

providing a lease to access a machine of the distributed system;

determining whether the lease requires an extension;

sending a renewal request to extend the lease; and

detecting an event preventing access to the machine based on a tailure to receive a new lease in response to the renewal request.

3. The method of

claim 2

, further comprising the step of:

performing a recovery routine upon detection of the event preventing access to the machine.