Using message-passing with procedural code in a database kernel

• US 10,740,317 B2
• Filed: 05/16/2017
• Issued: 08/11/2020
• Est. Priority Date: 10/24/2013
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP SE
• Inventors: Schreter, Ivan
• Primary Examiner(s): Uddin, Md I
• Application Number:
  US15/596,998
• Publication Number:
  US 20170262487A1
• Time in Patent Office: 1,183 Days
• Field of Search: 718105, 707607, 707695, 707692
• CPC Class Codes: G06F 16/21 Design, administration or maintenance of databases
• CPC Class Codes: G06F 16/23 Updating
• CPC Class Codes: G06F 16/2315 Optimistic concurrency control
• CPC Class Codes: G06F 16/27 Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor
• CPC Class Codes: G06F 16/275 Synchronous replication
• CPC Class Codes: G06F 9/5083 Techniques for rebalancing the load in a distributed system
• CPC Class Codes: G06F 9/546 Message passing systems or structures, e.g. queues

Abstract

Each of a plurality of database objects can be assigned to a specific message-passing worker of a plurality of message-passing workers, each executing on a first logical core that shares with at least a second logical core one or more resources of a physical processor core of a plurality of physical processor cores. The second logical core can execute a job worker of a plurality of job workers that implement procedural code. Exclusive write access can be provided to a database object of the plurality of database objects via a message-passing worker of the plurality of message-passing workers while read-only access is provided to any database object of the plurality of database objects via any of the plurality of job workers. Operations can be executed by the message-passing worker in an order in which request messages are received in a message queue of the message-passing worker.

Claims

1. A system comprising:

at least one programmable processor comprising at least one physical core and a plurality of logical cores; and

at least one memory comprising instructions which, when executed by the at least one programmable processor, cause operations comprising;

designating, for use by a first message-passing worker of a plurality of message-passing workers, a first logical core from the plurality of logical cores;

assigning, to the first message-passing worker, a first set of database objects from a plurality of database objects in a database management system, the first message-passing worker having write access to the first set of database objects;

assigning, to a second message-passing worker of the plurality of message-passing workers, a second set of database objects from the plurality of database objects, the second message-passing worker having write access to the second set of database objects,

wherein the first message-passing worker and the second message-passing worker have simultaneous write access to at least one database object common to the first and second set of database objects;

wherein the database objects are mapped to the first and second message-passing workers for facilitating data access in a mixed-mode environment in which message-passing and procedural coding approaches are used concurrently within a same database kernel;

providing, via a job worker, read-only access to at least a portion of the plurality of database objects, wherein the read-only access executed via a dirty read with no locks to ensure data consistency using versioned objects and multi-version concurrency control to filter visible rows;

designating, for use by the job worker, a second logical core from the plurality of logical cores, the first and second logical cores sharing one or more resources of the at least one physical core; and

directing, via the job worker, a plurality of messages to a message queue of at least one of the first and second message-passing worker.

2. The system as in claim 1, wherein the first set of database objects comprises a database table, wherein the second set of database objects comprises a column in the database table, and wherein the first and second message-passing workers configured to modify a database object in the column of database objects.

3. The system as in claim 1, wherein the operations further comprise:

executing, by the first and second message-passing worker, operations on the first and second set of database objects, wherein the executing is based on an order of received requests in a message queue of the first message-passing worker.

4. The system as in claim 1, wherein the operations further comprise:

reassigning the plurality of database objects to equalize a load across the plurality of message-passing workers.

5. The system as in claim 4, wherein the operations further comprise:

receiving, by a rebalanced message-passing worker of the plurality of message-passing workers after the reassigning, a request message pertaining to a reassigned database object of the plurality of database objects, the reassigned database object formerly assigned to the rebalanced message-passing worker and currently assigned to a new message-passing worker of the plurality of message-passing workers; and

posting, by the rebalanced message-passing worker, the new request message into a message queue of the new message-passing worker.

6. The system as in claim 1, wherein the assigning to the first message-passing worker comprises at least one of a round-robin assignment of the plurality of database objects to the plurality of message-passing workers or a random assignment of the plurality of database objects to the plurality of message-passing workers.

7. The system as in claim 4, wherein the operations further comprise:

maintaining and monitoring performance statistics for each database object of the plurality of database objects, wherein the reassigning is performed in response to the maintaining and monitoring.

8. A computer program product comprising a non-transitory machine-readable medium storing instructions that, when executed by at least one programmable processor, causes operations comprising:

designating, for use by a first message-passing worker of a plurality of message-passing workers, a first logical core from a plurality of logical cores;

assigning, to the first message-passing worker, a first set of database objects from a plurality of database objects in a database management system, the first message-passing worker having write access to the first set of database objects;

assigning, to a second message-passing worker of the plurality of message-passing workers, a second set of database objects from the plurality of database objects, the second message-passing worker having write access to the second set of database objects,

wherein the first message-passing worker and the second message-passing worker have simultaneous write access to at least one database object common to the first and second set of database objects;

wherein the database objects are mapped to the first and second message-passing workers for facilitating data access in a mixed-mode environment in which message-passing and procedural coding approaches are used concurrently within a same database kernel;

providing, via a job worker, read-only access to at least a portion of the plurality of database objects, wherein the read-only access executed via a dirty read with no locks to ensure data consistency using versioned objects and multi-version concurrency control to filter visible rows;

designating, for use by the job worker, a second logical core from the plurality of logical cores, the first and second logical cores sharing one or more resources of the at least one physical core; and

directing, via the job worker, a plurality of messages to a message queue of at least one of the first and second message-passing worker.

9. The computer program product as in claim 8, wherein the first set of database objects comprises a database table, wherein the second set of database objects comprises a column in the database table, and wherein the first and second message-passing workers configured to modify a database object in the column of database objects.

10. The computer program product as in claim 8, wherein the operations further comprise:

executing, by the first and second message-passing worker, operations on the first and second set of database objects, wherein the executing is based on an order of received requests in a message queue of the first message-passing worker.

11. The computer program product as in claim 8, the operations further comprise:

reassigning the plurality of database objects to equalize a load across the plurality of message-passing workers.

12. The computer program product as in claim 11, wherein the operations further comprise:

receiving, by a rebalanced message-passing worker of the plurality of message-passing workers after the reassigning, a request message pertaining to a reassigned database object of the plurality of database objects, the reassigned database object formerly assigned to the rebalanced message-passing worker and currently assigned to a new message-passing worker of the plurality of message-passing workers; and

posting, by the rebalanced message-passing worker, the new request message into a message queue of the new message-passing worker.

13. A computer-implemented method comprising:

designating, for use by a first message-passing worker of a plurality of message-passing workers, a first logical core from the plurality of logical cores;

assigning, to the first message-passing worker, a first set of database objects from a plurality of database objects in a database management system, the first message-passing worker having write access to the first set of database objects;

assigning, to a second message-passing worker of the plurality of message-passing workers, a second set of database objects from the plurality of database objects, the second message-passing worker having write access to the second set of database objects,

wherein the first message-passing worker and the second message-passing worker have simultaneous write access to at least one database object common to the first and second set of database objects;

wherein the database objects are mapped to the first and second message-passing workers for facilitating data access in a mixed-mode environment in which message-passing and procedural coding approaches are used concurrently within a same database kernel;

providing, via a job worker, read-only access to at least a portion of the plurality of database objects, wherein the read-only access executed via a dirty read with no locks to ensure data consistency using versioned objects and multi-version concurrency control to filter visible rows;

designating, for use by the job worker, a second logical core from the plurality of logical cores, the first and second logical cores sharing one or more resources of the at least one physical core; and

directing, via the job worker, a plurality of messages to a message queue of at least one of the first and second message-passing worker.

14. The computer-implemented method as in claim 13, wherein the first set of database objects comprises a database table, wherein the second set of database objects comprises a column in the database table, and wherein the first and second message-passing workers configured to modify a database object in the column of database objects.

15. The computer-implemented method as in claim 13, wherein the operations further comprise:

executing, by the first and second message-passing worker, operations on the first and second set of database objects, wherein the executing is based on an order of received requests in a message queue of the first message-passing worker.

16. The computer-implemented method as in claim 13, wherein the operations further comprise:

reassigning the plurality of database objects to equalize a load across the plurality of message-passing workers.

17. The computer-implemented method as in claim 16, wherein the operations further comprise:

receiving, by a rebalanced message-passing worker of the plurality of message-passing workers after the reassigning, a request message pertaining to a reassigned database object of the plurality of database objects, the reassigned database object formerly assigned to the rebalanced message-passing worker and currently assigned to a new message-passing worker of the plurality of message-passing workers; and

posting, by the rebalanced message-passing worker, the new request message into a message queue of the new message-passing worker.