Rendezvous-based optimistic concurrency control

Patent metadata

Field	Value
Publication number	US-2016196295-A1
Application number	US-201514591053-A
Country	US
Kind code	A1
Filing date	Jan 7, 2015
Priority date	Jan 7, 2015
Publication date	Jul 7, 2016
Grant date	—

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 a subscriber when a third transaction operation of the set of transaction operations modifies the first record; and 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; 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 . The method of claim 1 , further comprising:
committing the transaction based, at least in part, upon receiving a publication of a transaction commit timestamp before receiving a committed write publication.

6 . The method of claim 1 , further comprising:
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.

7 . 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 a subscriber when a third transaction operation of the set of transaction operations modifies the first record; and 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.

8 . The computer program product of claim 7 , wherein the transaction is divided into two queues, a message queue and an operation queue.

9 . The computer program product of claim 7 , 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.

10 . The computer program product of claim 7 , 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.

11 . The computer program product of claim 7 , further comprising:
fifth 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.

12 . The computer program product of claim 7 , further comprising:
fifth 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.

13 . 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 a subscriber when a third transaction operation of the set of transaction operations modifies the first record; and 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.

14 . The computer system of claim 13 , wherein the transaction is divided into two queues, a message queue and an operation queue.

15 . The computer system of claim 13 , 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.

16 . The computer system of claim 13 , 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.

17 . The computer system of claim 13 , the program instructions further include:
fifth 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.

18 . The computer system of claim 13 , the program instructions further include:
fifth 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.

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

• G06F17/30592

  Physics · mapped topic

• G06F17/30351 Primary

  Physics · mapped topic

• G06F17/30377

  Physics · mapped topic