APPLICATION INSTANCE AND QUERY STORES

• US 20120030169A1
• Filed: 07/27/2010
• Published: 02/02/2012
• Est. Priority Date: 07/27/2010
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Allen, Nicholas A., Taylor, John A., Paramasivam, Kartik, Shukla, Dharma
• Granted Patent: US 8,903,782 B2
• Time in Patent Office: Days
• US Class Current: 707/627
• CPC Class Codes: G06F 16/23 Updating

Abstract

An instance persistence command for an update to a state of an instance of an application can be issued. In response to the persistence command, a transaction with an instance store can be initiated. As part of the transaction, a first representation of the update can be stored in the instance store and a second representation of the update can be stored in a queue. The transaction can be committed after storing the first and second representations. After the transaction is committed, the second representation can be processed to store a third representation of the update in a query store. Application instance state information in the query store can be updated and queried without locking the instance store so that such operations in the query store can be performed asynchronously with operations in the instance store.

Claims

1. A computer-implemented method, comprising:

issuing an instance persistence command for an update to a state of an instance of an application;

initiating a transaction with an instance store in response to the persistence command;

as part of the transaction, storing a first representation of the update in the instance store; and

as part of the transaction, storing a second representation of the update in a queue;

committing the transaction after storing the first representation and the second representation; and

after committing the transaction, processing the second representation of the update to store a third representation of the update in a query store.

2. The method of claim 1, wherein the transaction includes locking at least a portion of the instance store, but processing the second representation of the update is done without locking the instance store.

3. The method of claim 1, further comprising querying the third representation in the query store without locking the instance store.

4. The method of claim 1, wherein the second representation of the update is different from the first representation of the update.

5. The method of claim 4, further comprising supplementing the second representation of the update with application data that is not present in the first representation.

6. The method of claim 4, wherein processing the second representation of the update to store a third representation of the update in a query store comprises applying a filter to the second representation.

7. One or more computer-readable storage media having computer-executable instructions embodied thereon that, when executed by at least one processor, cause the at least one processor to perform acts comprising:

receiving from a query service a subscription request for results of application instance state updates, the subscription request comprising a filter;

receiving from a results queue a set of results of one or more application instance state updates;

applying the filter to the set of results from the results queue;

publishing to the query service one or more results of the set that meet a set of one or more requirements of the filter; and

storing in a query store one or more representations of one or more application instance state updates corresponding to the one or more results published to the query service.

8. The one or more computer-readable storage media of claim 7, wherein the acts further comprise storing in an instance store representations of application instance state updates corresponding to the set of results, wherein publishing to the query service and storing in the query store are done without locking the instance store.

9. The one or more computer-readable storage media of claim 8, wherein the acts further comprise:

receiving from the query service a request to synchronize with the instance store;

in response to the request to synchronize, requesting synchronization information from the instance store;

receiving the requested synchronization information from the instance store; and

forwarding at least a portion of the synchronization information to the query service.

10. The one or more computer-readable storage media of claim 9, wherein the acts further comprise using at least a portion of the synchronization information to synchronize at least a portion of a query store with at least a portion of the instance store.

11. The one or more computer-readable storage media of claim 7, wherein the acts further comprise:

issuing an instance persistence command for an update to a state of an application instance of an application;

initiating a transaction between the application and an instance store in response to the persistence command;

as part of the transaction, storing a first representation of the update in the instance store; and

as part of the transaction, storing a second representation of the update in the results queue;

committing the transaction; and

after committing the transaction, processing the second representation of the update to store a third representation of the update in the query store.

12. A computer system comprising:

an application host configured to run one or more application instances;

an instance store connected to the application host;

a results queue connected to the application host, wherein the application host, the instance store, and the results queue are configured to participate in transactions in response to instance persistence commands for updates to one or more states of one or more instances of an application running on the application host, each of the transactions comprising;

initiating the transaction in response to an instance persistence command for an update to a state of an application instance;

storing a first representation of the update in the instance store;

storing a second representation of the update in the results queue; and

committing the transaction;

a publisher connected to the queue;

one or more query services connected to the publisher, the publisher being configured to process update representations in the results queue to publish results from the queue to the one or more query services, the processing and publishing being done without locking the instance store; and

one or more query stores connected to the one or more query services, each of the one or more query services being configured to respond to received results by storing in a query store representations of updates corresponding to the received results.

13. The computer system of claim 12, wherein at least one of the one or more query stores is configured to service queries from an application tool.

14. The computer system of claim 12, wherein the results queue is connected to the application host via the instance store.

15. The computer system of claim 12, wherein the application host comprises a persistence provider that is connected to the instance store.

16. The computer system of claim 12, wherein the transaction comprises supplementing the second representation with application data that is not present in the first representation.

17. The computer system of claim 12, wherein:

the one or more query services are configured to send subscription information to the publisher; and

the publisher is configured to apply the subscription information to publish results to the query services.

18. The computer system of claim 17, wherein at least one of the one or more query services is configured to send to the publisher subscription information that comprises a filter.

19. The computer system of claim 12, wherein:

a query service of the one or more query services is configured to send to the publisher a request to synchronize with the instance store;

the publisher is configured to respond to the request to synchronize by sending to the instance store a request for synchronization information;

the instance store is configured to respond to the request for synchronization information by sending the requested synchronization information to the queue; and

the publisher is configured to publish the synchronization information from the queue to at least one of the one or more query services.

20. The computer system of claim 19, wherein at least one of the one or more query services is configured to use the synchronization information to synchronize at least a portion of a query store with at least a portion of the instance store.