Rendezvous-based optimistic concurrency control

Patent metadata

Field	Value
Publication number	US-9679003-B2
Application number	US-201514591053-A
Country	US
Kind code	B2
Filing date	Jan 7, 2015
Priority date	Jan 7, 2015
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

A concurrent transaction validate phase with the transaction operations read, compute, and write allows for a rendezvous-based optimistic concurrency control process.

First claim

What is claimed is:

1. A method for processing a transaction, the method comprising:
decoupling a validation operation from one or more of a read operation, a write operation, and a compute operation of a transaction to establish a set of transaction operations;
responsive to a first transaction operation of a set of transaction operations reading a first record, issuing a read subscription;
responsive to a second transaction operation of the set of transaction operations modifying the first record, issuing a write publication;
notifying the read subscription when a third transaction operation of the set of transaction operations modifies the first record;
entering a commit phase of the transaction based upon the following conditions: (i) the read subscription and the write publication are both complete; and (ii) the set of transaction operations are complete;
committing the transaction based, at least in part, upon receiving a publication of a transaction commit timestamp before receiving a committed write publication; and
aborting the transaction based, at least in part, upon receiving a committed write publication for a transaction operation not within the set of transaction operations that modified the first record;
wherein:
at least the issuing a read subscription, issuing a write publication, and committing the transaction steps are performed by computer software running on computer hardware.

2. The method of claim 1 , wherein the transaction is divided into two queues, a message queue and an operation queue.

3. The method of claim 1 , wherein the validation operation is performed asynchronous to a performance of the one or more of a read operation, a write operation, and a compute operation of the transaction.

4. The method of claim 1 , further comprising:
requesting a transaction timestamp based upon the following conditions: (i) the read subscription and the write publication are both complete; and (ii) the set of transaction operations are complete.

5. A computer program product for processing a transaction, the computer program product comprising a computer readable storage medium having stored thereon:
first program instructions programmed to decouple a validation operation from one or more of a read operation, a write operation, and a compute operation of a transaction to establish a set of transaction operations;
second program instructions programmed to, responsive to a first transaction operation of a set of transaction operations reading a first record, issue a read subscription;
third program instructions programmed to, responsive to a second transaction operation of the set of transaction operations modifying the first record, issue a write publication;
fourth program instructions programmed to notify the read subscription when a third transaction operation of the set of transaction operations modifies the first record;
fifth program instructions programmed to enter a commit phase of the transaction based upon the following conditions: (i) the read subscription and the write publication are both complete; and (ii) the set of transaction operations are complete;
sixth program instructions programmed to commit the transaction based, at least in part, upon receiving a publication of a transaction commit timestamp before receiving a committed write publication; and
seventh program instructions programmed to abort the transaction based, at least in part, upon receiving a committed write publication for a transaction operation not within the set of transaction operations that modified the first record.

6. The computer program product of claim 5 , wherein the transaction is divided into two queues, a message queue and an operation queue.

7. The computer program product of claim 5 , wherein the validation operation performed asynchronous to a performance of the one or more of a read operation, a write operation, and a compute operation of the transaction.

8. The computer program product of claim 5 , further comprising:
fifth program instructions programmed to request a transaction timestamp based upon the following conditions: (i) the read subscription and the write publication are both complete; and (ii) the set of transaction operations are complete.

9. A computer system for processing a transaction, the computer system comprising:
a processor(s) set; and
a computer readable storage medium;
wherein:
the processor set is structured, located, connected, and/or programmed to run program instructions stored on the computer readable storage medium; and
the program instructions include:
first program instructions programmed to decouple a validation operation from one or more of a read operation, a write operation, and a compute operation of a transaction to establish a set of transaction operations;
second program instructions programmed to, responsive to a first transaction operation of a set of transaction operations reading a first record, issue a read subscription;
third program instructions programmed to, responsive to a second transaction operation of the set of transaction operations modifying the first record, issue a write publication;
fourth program instructions programmed to notify the read subscription when a third transaction operation of the set of transaction operations modifies the first record;
fifth program instructions programmed to enter a commit phase of the transaction based upon the following conditions: (i) the read subscription and the write publication are both complete; and (ii) the set of transaction operations are complete;
sixth program instructions programmed to commit the transaction based, at least in part, upon receiving a publication of a transaction commit timestamp before receiving a committed write publication; and
seventh program instructions programmed to abort the transaction based, at least in part, upon receiving a committed write publication for a transaction operation not within the set of transaction operations that modified the first record.

10. The computer system of claim 9 , wherein the transaction is divided into two queues, a message queue and an operation queue.

11. The computer system of claim 9 , wherein the validation operation is performed asynchronous to a performance of the one or more of a read operation, a write operation, and a compute operation of the transaction.

12. The computer system of claim 9 , the program instructions further include:
fifth program instructions programmed to request a transaction timestamp based upon the following conditions: (i) the read subscription and the write publication are both complete; and (ii) the set of transaction operations are complete.

Assignees

• IBM

Inventors

• Bhattacharjee Bishwaranjan
• Canim Mustafa
• Sadoghi Hamedani Mohammad

Classifications

• G06F16/2315 Primary

  Optimistic concurrency control · CPC title

• G06F16/2379

  Updates performed during online database operations; commit processing · CPC title

• G06F17/30351 Primary

  Physics · mapped topic

• G06F17/30377

  Physics · mapped topic