Preferentially Retaining Memory Pages Using a Volatile Database Table Attribute

Patent metadata

Field	Value
Publication number	US-2016171022-A1
Application number	US-201414566326-A
Country	US
Kind code	A1
Filing date	Dec 10, 2014
Priority date	Mar 26, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

A respective volatility attribute associated with each of one or more tables of a computerized database is used to determine circumstances under which a page of table data is paged out of memory, by preferentially retaining pages from volatile database tables in memory. Various optional additional uses of a volatility attribute to manage a database are disclosed. Preferably, database parameters are automatically monitored over time and database table volatility state is automatically determined and periodically adjusted.

First claim

What is claimed is:

1 . A method for managing a computerized database, comprising the following executed by at least one computer system:
storing at least one respective volatility attribute for each of at least one database table of said computerized database, each volatility attribute expressing volatility of at least a portion of a respective database table of said computerized database; determining circumstances under which a page of data temporarily stored in memory of said at least one computer system and containing data of a first database table of said computerized database is paged out of said memory using the at least one volatility attribute corresponding to the first database table.

2 . The method for managing a computerized database of claim 1 , further comprising:
monitoring at least one respective parameter of each said database table of said computerized database over at least one time interval and saving monitored parameter data with respect to the respective database table; and determining a respective volatility state of each said database table using the saved monitored parameter data to automatically generate said at least one respective volatility attribute for each said database table.

3 . The method for managing a computerized database of claim 2 , further comprising:
computing a respective figure of merit representing volatility of the at least a portion of the respective database table for each of said at least one time interval.

4 . The method for managing a computerized database of claim 1 , wherein said computerized database supports the SQL database language and said at least volatility attribute comprises an SQL VOLATILE attribute.

5 . The method for managing a computerized database of claim 1 , wherein said determining circumstances under which a page of data temporarily stored in memory of said at least one computer system and containing data of a first database table of said computerized database is paged out of said memory comprises preferentially retaining a page of data in memory if the at least one volatility attribute corresponding to the first database table indicates that at least a portion of the first database table containing data stored in the first page is volatile.

6 . The method for managing a computerized database of claim 5 , wherein said preferentially retaining a page of data in memory comprises pinning the page of data to prevent eviction from memory.

7 . The method for managing a computerized database of claim 5 , further comprising:
determining a respective memory retention priority for each of a plurality of database tables or portions of a database table, wherein pages of data from each database table of portion of a database table are preferentially retained according to the respective memory retention priority.

8 . The method for managing a computerized database of claim 7 , wherein the memory retention priority is determined by computing a respective figure of merit for each of the plurality of database tables or portions of a database table, each figure of merit being computed using at least one of: (a) a size of the corresponding database table or portion of a database table, and (b) a quantitative value expressing volatility of the corresponding database table or portion of a database table.

9 . The method for managing a computerized database of claim 1 , wherein said volatility attribute comprises a quantitative value.

10 - 20 . (canceled)

Assignees

• IBM

Inventors

• Konik Rafal P
• Mittelstadt Roger A
• Muras Brian R
• Theuer Mark W

Classifications

• G06F17/30309 Primary

  Physics · mapped topic

• G06F17/30339

  Physics · mapped topic

• G06F16/24542

  Plan optimisation · CPC title

• G06F16/13

  File access structures, e.g. distributed indices (arrangements of input from, or output to, record carriers G06F3/06) · CPC title

• G06F16/116 Primary

  Details of conversion of file system types or formats · CPC title