State management for transactional backup consistency
First Claim
1. A computer-readable storage medium having computer-executable instructions, which when stored in a system memory of a computer and executed by a processing unit of the computer perform actions, comprising:
- receiving a shadow copy service request to provide a consistent view of a set of resources managed by the computer, a first resource manager potentially involved in a transaction affecting at least one resource of the set of resources, the first resource manager executed at least in part by the processing unit;
allowing the first resource manager to enter the transaction after the shadow copy service request is received if the transaction would not cause the first resource manager to enter a problematic state that makes the view inconsistent;
preventing the first resource manager from entering into the transaction after the shadow copy service request is received if the transaction would cause the first resource manager to enter a problematic state that makes the view inconsistent;
creating a shadow copy of at least a first resource after the consistent view is available; and
performing a recovery of the shadow copy.
3 Assignments
0 Petitions
Accused Products
Abstract
Aspects of the subject matter described herein relate to transactions. In aspects, a consistency requester such as a shadow copy service requests to have a consistent view of a set of resources. In response, transactions that are in a problematic state are allowed to exit the problematic state while new and existing transactions that are not in the problematic state are allowed to perform any work except work that takes them into the problematic state. After no transactions are in the problematic state, a consistent view of the set of resources is available. This view may be used by the consistency requester as desired. Afterwards, the consistency requester may indicate that a consistent view is no longer needed. Transactions are then allowed to enter the problematic state. Transactions may also be allowed to enter the problematic state if a timeout elapses.
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Citations
20 Claims
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1. A computer-readable storage medium having computer-executable instructions, which when stored in a system memory of a computer and executed by a processing unit of the computer perform actions, comprising:
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receiving a shadow copy service request to provide a consistent view of a set of resources managed by the computer, a first resource manager potentially involved in a transaction affecting at least one resource of the set of resources, the first resource manager executed at least in part by the processing unit; allowing the first resource manager to enter the transaction after the shadow copy service request is received if the transaction would not cause the first resource manager to enter a problematic state that makes the view inconsistent; preventing the first resource manager from entering into the transaction after the shadow copy service request is received if the transaction would cause the first resource manager to enter a problematic state that makes the view inconsistent; creating a shadow copy of at least a first resource after the consistent view is available; and performing a recovery of the shadow copy. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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13. A method implemented at least in part by computer executable instructions stored in a system memory of a computer and executed by a processing unit of the computer, the method comprising:
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requesting that resource managers, executed at least in part by the processing unit, be prevented from entering a problematic state with respect to transactions affecting a set of resources stored on a set of resource stores accessible to the computer, the resource managers not prevented from entering into transactions that cause the resource managers not to enter a problematic state; waiting until an earliest of a timeout period elapsing or until all of the resource managers that are in the problematic state exit the problematic state; if the timeout period has not elapsed, receiving a notification that indicates that no resource managers are in the problematic state; and if the timeout period has elapsed, refraining from taking a shadow copy of the set of resources. - View Dependent Claims (14, 15, 16, 17, 18)
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19. In a computing environment having system memory of a computer configured to store computer executable instructions and a processing unit of a computer configured to execute the computer executable instructions, an apparatus, comprising:
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a first resource manager, configured to manage at least one resource stored on at least one resource store accessible to the computer; a consistency requestor, configured to request a consistent view of the at least one resource; and a transaction manager, configured to receive the request and in response thereto prevent the first resource manager from entering into a transaction after the request is received if the transaction would cause the first resource manager to enter a problematic state that makes the view inconsistent and allow the first resource manager to enter a second transaction after the request is received if the second transaction would not cause the first resource manager to enter a problematic state that makes the view inconsistent, the consistency requester configured to create a shadow copy of the at least one resource after the consistent view is available such that a recovery of the shadow copy can be performed without the involvement of the transaction manager, at least some of at least one of the first resource manager, the consistency requestor and the transaction manager implemented at least in part by the processing unit. - View Dependent Claims (20)
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Specification