Database redistribution in dynamically-configured database systems

• US 9,141,646 B1
• Filed: 12/30/2011
• Issued: 09/22/2015
• Est. Priority Date: 12/30/2011
• Status: Active Grant

• Current Assignee: Teradata Corporation
• Original Assignee: Teradata US, Inc. (Teradata Corporation)
• Inventors: Shatdal, Ambuj
• Primary Examiner(s): BROWN, SHEREE N
• Application Number:
  US13/341,889
• Time in Patent Office: 1,362 Days
• Field of Search: 707/803
• US Class Current: 1/1
• CPC Class Codes: G06F 16/1727 Details of free space management performed by the file system saving storage space on storage systems G06F3/0608; management of blocks in storage devices G06F3/064
• CPC Class Codes: G06F 16/21 Design, administration or maintenance of databases
• 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

Abstract

A database system may implement resource management for redistribution of stored database information in additional database resources. Resource management may include detection of the presence of additional database resources, such as storage and processing resources. Based on conditions associated with the additional resources and database information selected for potential redistribution, resource management may include a determination as to whether or not redistribution of the database information is to be performed. Resource management may include a cost-benefit analysis to determine if redistribution of database information is to be performed. The cost-benefit analysis may be based on factors related to both the additional resources and the database information being considered for redistribution.

Claims

1. A resource management tool for a database system, the resource management tool comprising:

a memory device; and

a processor in communication with the memory device, the processor configured to;

detect availability of additional database resources to the database system in response to addition of the additional database resources to the database system, wherein the additional database resources include at least one of additional processing resources and additional storage resources;

identify a database object associated with original database resources of the database system to be redistributed from the original database resources to the additional database resources, wherein the original database resources include at least one of processing resources and storage resources;

determine presence of at least one condition associated with at least one of the additional database resources and the identified database object; and

redistribute at least a portion of the database object from the original database resources to the additional database resources in response to the presence of the at least one condition, wherein the redistribution disassociates the at least a portion of the database object from the original database resources and associates the at least a portion of the database object with the additional database resources.

2. The resource management tool of claim 1, wherein the at least one condition is associated with a ratio of additional database resources to a combination of the additional database resources and the original database resources.

3. The resource management tool of claim 2, wherein:

the original database resources comprise a first plurality of processing units;

the additional database resources comprise a second plurality of processing units; and

the at least one condition comprises a ratio of a number of the second plurality of processing units to a sum of the number of the second plurality of processing units and a number of the first plurality of processing units.

4. The resource management tool of claim 3, wherein:

the identified database object is a database table; and

the at least one condition is further associated with an expected number of accesses of the database table.

5. The resource management tool of claim 4, wherein the predetermined condition is the expected number of accesses of the database table being greater than:

μ

+1/μ

−

1

where μ

is the ratio of the number of the second plurality of processing units to the sum of the number of the second plurality of processing units and the number of the first plurality of processing units.

6. The resource management tool of claim 1, wherein the identified database object is a database table, and wherein the processor is further configured to generate a signal indicative of detection of the presence of the at least one condition.

7. The resource management tool of claim 6, wherein the processor is further configured to:

transmit, to a user interface, the signal indicative of detection of the presence of the at least one condition;

receive a second signal from the user interface; and

redistribute at least a portion of the database table from the original database resources to the additional database resources in response to receipt of the second signal from the user interface.

8. A method of managing resources for a database system stored in a memory device, the method comprising:

detecting, with a processor, availability of additional database resources to the database system comprising original database resources in response to addition of the additional database resources to the database system, wherein the additional database resources include at least one of additional processing resources and additional storage resources;

identifying, with the processor, database information associated with the original database resources of the database system to be redistributed from the original database resources to the additional database resources, wherein the original database resources include at least one of processing resources and storage resources;

determining, with the processor, presence of at least one condition associated with at least one of the additional database resources and the identified database information; and

redistributing, with the processor, at least a portion of the database information from the original database resources to the additional database resources in response to the determination of the at least one condition, wherein the redistribution disassociates the at least a portion of the database object from the original database resources and associates the at least a portion of the database object with the additional database resources.

9. The method of claim 8, wherein the determining, with the processor, the presence of the at least one condition comprises:

determining, with the processor, a cost value associated with redistributing the at least a portion of the database information;

determining, with the processor, a benefit value associated with redistributing the at least a portion of the database information; and

determining, with the processor, when the benefit value is greater than the cost value.

10. The method of claim 9, wherein:

the original database resources comprise a first plurality of processors and the additional database resources comprise a second plurality of processors;

identifying, with the processor, database information associated with the original database resources of the database system to be redistributed comprises identifying, with the processor, a database table associated with the original database resources of the database system to be redistributed; and

determining, with the processor, the cost value comprises determining, with the processor, the cost value based on at least one of a number of the first plurality of processors, a number of the second plurality of processors, a cost value associated with reading a row of the database table, and cardinality of the database table.

11. The method of claim 9, wherein:

the original database resources comprise a first plurality of processors and the additional database resources comprise a second plurality of processors;

identifying, with the processor, database information associated with original database resources of the database system to be redistributed comprises identifying, with the processor, a database table associated with the original database resources of the database system to be redistributed; and

determining, with the processor, the benefit value comprises determining, with the processor, the benefit value based on at least one of the first plurality of processors, the second plurality of processors, a cost value associated with reading a row of the database table, cardinality of the database table, and an access value indicative of an amount of expected accesses of the database table.

12. The method of claim 8, wherein:

the original database resources comprise a first plurality of processors and the additional database resources comprise a second plurality of processors; and

determining, with the processor, presence of the at least one condition comprises determining, with the processor, a ratio of the second plurality of processors to a combination of the first plurality of processors and the second plurality of processors.

13. The method of claim 12, wherein:

identifying, with the processor, database information associated with original database resources of the database system to be redistributed comprises identifying, with the processor, a database table associated with the original database resources of the database system to be redistributed; and

determining, with the processor, presence of at least one condition further comprises determining, with the processor, when an expected number of accesses of the database table is greater than;

1/(μ

−

1)

where μ

is the ratio of the number of the second plurality of processing units to the sum of the number of the second plurality of processing units and the number of the first plurality of processing units.

14. The method of claim 8 further comprising:

receiving, with the processor, indication that at least a portion of the additional resources are to become unavailable; and

redistributing, with the processor, the database information from the at least a portion of the additional resources to at least one of the original database resources and available additional resources in response to the indication that at least a portion of the additional resources are to become unavailable.

15. A non-transitory computer-readable medium encoded with a plurality of instructions executable by a processor, the plurality of instructions comprising:

instructions to detect presence of additional database resources added to a database system comprising original database resources in response to addition of the additional database resources to the database system, wherein the additional database resources include at least one of additional processing resources and additional storage resources;

instructions to identify database information associated with the original database resources of the database system to be redistributed from the original database resources to the additional database resources, wherein the original database resources include at least one of processing resources and storage resources;

instructions to determine presence of at least one condition associated with at least one of the additional database resources and the identified database information; and

instructions to distribute at least a portion of the database information from the original database resources to the additional database resources in response to the determination of the at least one condition, wherein the distribution disassociates the at least a portion of the database object from the original database resources and associates the at least a portion of the database object with the additional database resources.

16. The non-transitory computer-readable medium of claim 15, wherein the instructions to determine the presence of the at least one condition comprise:

instructions to determine a cost value associated with redistributing the at least a portion of the database information;

instructions to determine a benefit value associated with redistributing the at least a portion of the database information; and

instructions to determine, with the processor, when the benefit value is greater than the cost value.

17. The non-transitory computer-readable medium of claim 16, wherein:

the original database resources comprise a first plurality of processors and the additional database resources comprise a second plurality of processors;

the instructions to identify database information associated with the original database resources of the database system to be redistributed comprise instructions to identify a database table associated with the original database resources of the database system to be redistributed; and

the instructions to determine a cost value comprise instructions to determine the cost value based on at least one of a number of the first plurality of processors, a number of the second plurality of processors, a cost value associated with reading a row of the database table, and cardinality of the database table.

18. The non-transitory computer-readable medium of claim 16, wherein:

the original database resources comprise a first plurality of processors and the additional database resources comprise a second plurality of processors;

the instructions to identify database information associated with the original database resources of the database system to be redistributed comprise instructions to identify a database table associated with the original database resources of the database system to be redistributed; and

the instructions to determine the benefit value comprise instructions to determine the benefit value based on at least one of the first plurality of processors, the second plurality of processors, a cost value associated with reading a row of the database table, cardinality of the database table, and an access value indicative of an amount of expected accesses of the database table.

19. The non-transitory computer-readable medium of claim 16, wherein:

the original database resources comprise a first plurality of processors and the additional database resources comprise a second plurality of processors; and

the instructions to determine the presence of at least one condition further comprise determining, with the processor, when the expected number of accesses of the database table is greater than;

μ

+1/μ

−

1

where μ

is the ratio of the number of the second plurality of processing units to the sum of the number of the second plurality of processing units and the number of the first plurality of processing units.

20. The non-transitory computer-readable medium of claim 15, wherein the plurality of instructions further comprises:

instructions to determine that at least a portion of the additional resources are to become unavailable; and

instructions to redistribute the database information from the at least a portion of the additional resources to at least one of the original database resources and available additional resources in response to the determination that the at least a portion of the additional resources are to become unavailable.