PROGRAM, METHOD, AND APPARATUS FOR DYNAMICALLY ALLOCATING SERVERS TO TARGET SYSTEM

• US 20090172168A1
• Filed: 03/10/2009
• Published: 07/02/2009
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Koike, Kunimasa, Tsuchiya, Satoshi, Sonoda, Masataka, Sekiguchi, Atsuji
• Granted Patent: US 8,661,130 B2
• Time in Patent Office: Days
• US Class Current: 709/226
• CPC Class Codes: G06F 11/004 Error avoidance G06F11/07 and subgroups take precedence
• CPC Class Codes: G06F 11/008 Reliability or availability analysis
• CPC Class Codes: G06F 11/2025 using centralised failover control functionality
• CPC Class Codes: G06F 11/2028 eliminating a faulty processor or activating a spare
• CPC Class Codes: G06F 11/2041 with more than one idle spare processing component
• CPC Class Codes: G06F 11/3055 Monitoring arrangements for monitoring the status of the computing system or of the computing system component, e.g. monitoring if the computing system is on, off, available, not available error or fault processing without redundancy G06F11/0703; error detection or correction by redundancy in data representation G06F11/08; error detection or correction by redundancy in operation G06F11/14; error detection or correction by redundancy in hardware G06F11/16
• CPC Class Codes: G06F 11/3409 for performance assessment
• CPC Class Codes: G06F 11/3442 for planning or managing the needed capacity
• CPC Class Codes: G06F 2201/875 Monitoring of systems including the internet
• CPC Class Codes: G06F 2209/5019 Workload prediction
• CPC Class Codes: G06F 9/5061 Partitioning or combining of resources
• CPC Class Codes: G06F 9/5083 Techniques for rebalancing the load in a distributed system
• CPC Class Codes: H04L 41/147 for predicting network behaviour
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers

Abstract

Server management data describes observed operating condition of a pool of spare servers. Based on a demand forecast of a specific target system, a dynamic allocation period is determined as a period during which the target system needs additional server resources to handle an expected demand. Based on the dynamic allocation period and server management data, a set of allocation candidates are nominated from the spare server pool, by eliminating therefrom spare servers which are likely to fail during the dynamic allocation period. An appropriate allocation candidate is then selected for allocation to the target system, such that the selected candidate will satisfy a specified requirement during its allocation period.

Claims

1. A computer-readable storage medium encoded with a server allocation program that performs, when executed on a computer, a process of allocating servers to a target system, the process comprising:

monitoring operating condition of spare servers that belong to a spare server pool;

storing and managing server management data which describes the operating condition of the spare servers, together with information about performance of the spare servers;

determining, based on demand forecast data or previously specified data about the target system, a dynamic allocation period during which the target system is expected to need allocation of the spare servers;

estimating failure probabilities of the individual spare servers during the dynamic allocation period, based on the stored server management data;

nominating a set of allocation candidates from the spare server pool according to the estimated failure probabilities of the individual spare servers during the dynamic allocation period; and

selecting, based on the stored server management data, which allocation candidate to allocate to the target system, such that the selected allocation candidate will enable the target system to satisfy a specified requirement during the dynamic allocation period.

2. The computer-readable storage medium according to claim 1, wherein:

the server management data includes mean time between failure (MTBF) or mean time to failure (MTTF) of each spare server, and operating time elapsed since startup of each spare server; and

said nominating calculates a remaining operating time from the operating time and the MTBF or MTTF of each spare server, and determines a failure probability of each spare server by comparing the remaining operating time thereof with the dynamic allocation period.

3. The computer-readable storage medium according to claim 2, wherein said nominating eliminates a spare server from the set of allocation candidates if the remaining operating time of that spare server will be exhausted before the dynamic allocation period expires.

4. The computer-readable storage medium according to claim 1, wherein said nominating eliminates a spare server from the set of allocation candidates if that spare server fails to satisfy a previously specified allocation condition.

5. The computer-readable storage medium according to claim 4, wherein:

the allocation condition includes a cost requirement; and

said nominating eliminates a spare server from the set of allocation candidates if that spare server fails to satisfy the cost requirement.

6. The computer-readable storage medium according to claim 1, wherein:

the target system comprises multiple layers of servers; and

said selecting is performed for each of the layers.

7. The computer-readable storage medium according to claim 1, wherein:

the allocation condition includes a performance requirement that the target system is supposed to satisfy; and

said selecting selects an allocation candidate that compensates for shortage of processing capacity of the target system during the dynamic allocation period.

8. The computer-readable storage medium according to claim 7, wherein said selecting considers another allocation condition other than the performance requirement when selecting an allocation candidate.

9. The computer-readable storage medium according to claim 7, wherein:

the target system comprises multiple layers of servers; and

said selecting comprises;

identifying a layer exhibiting a lowest reliability, among the layers that fall short of processing capacity,

allocating an allocation candidate with a highest reliability to the identified layer,

assessing performance attained by the target system as a result of said allocating, and

repeating a reliability-based server allocation by using the other allocation candidates if the attained performance fails to satisfy the performance requirement.

10. The computer-readable storage medium according to claim 1, wherein:

the specified requirement includes a performance requirement and a reliability requirement that the target system is supposed to satisfy;

the target system comprises a working system and a backup system; and

said selecting comprises;

allocating the selected allocation candidate to the working system of the target system,

calculating, by using a predetermined reliability index, reliability that the target system including the allocated allocation candidate is expected to attain during the dynamic allocation period, and

allocating one of the other allocation candidates to the backup system of the target system if the calculated reliability fails to satisfy the reliability requirement.

11. The computer-readable storage medium according to claim 10, wherein:

the target system comprises multiple layers of servers; and

said allocating to the backup system comprises;

identifying a layer exhibiting a lowest reliability,

allocating an allocation candidate with a highest reliability to the identified layer,

assessing reliability attained by the target system as a result of said allocating, and

repeating a reliability-based server allocation by using the other allocation candidates if the attained reliability fails to satisfy the reliability requirement.

12. The computer-readable storage medium according to claim 11, wherein said allocating to the backup system comprises:

selecting an allocation candidate whose performance is equal to or greater than a server belonging to the working system of the target system.

13. The computer-readable storage medium according to claim 1, the process further comprising:

storing previously an alternative to the specified requirement; and

determining which allocation candidate to allocate to the target system by selecting an allocation candidate that satisfies the alternative to the specified requirement, when none of the allocation candidates can satisfy the specified requirement.

14. The computer-readable storage medium according to claim 13, wherein:

the alternative relaxes the specified requirement; and

said selecting uses the relaxed requirement according to the alternative.

15. The computer-readable storage medium according to claim 1, the process further comprising:

producing an alternative condition to replace the specified requirement if said selecting is unable to select an allocation candidate that satisfies the specified requirement; and

presenting the alternative condition to a user of the target system.

16. The computer-readable storage medium according to claim 14, the process further comprising:

producing a plurality of different alternatives to replace the specified requirement.

17. A method for dynamically allocating servers to a target system, the method comprising:

monitoring operating condition of spare servers that belong to a spare server pool;

storing and managing server management data which describes the operating condition of the spare servers, together with information about performance of the spare servers;

determining, based on demand forecast data or previously specified data about the target system, a dynamic allocation period during which the target system is expected to need allocation of the spare servers;

estimating failure probabilities of the individual spare servers during the dynamic allocation period, based on the stored server management data;

nominating a set of allocation candidates from the spare server pool according to the estimated failure probabilities of the individual spare servers during the dynamic allocation period; and

selecting, based on the stored server management data, which allocation candidate to allocate to the target system, such that the selected allocation candidate will enable the target system to satisfy a specified requirement during the dynamic allocation period.

18. An apparatus for dynamically allocating servers to a target system, the apparatus comprising:

a server manager which monitors operating condition of spare servers that belong to a spare server pool and manages server management data describing the operating condition of the spare servers, together with information about performance of the spare servers;

a server management data storage unit to store the server management data, together with the information about performance of the spare servers;

an allocation period management unit which determines, based on demand forecast data or previously specified data about the target system, a dynamic allocation period during which the target system is expected to need allocation of the spare servers;

a server candidate nomination unit which estimates failure probabilities of the individual spare servers during the dynamic allocation period, based on the server management data stored in the server management data storage unit, and nominates a set of allocation candidates from the spare server pool according to the estimated failure probabilities; and

a server selection unit which selects, based on the stored server management data, which allocation candidate to allocate to the target system, such that the selected allocation candidate will enable the target system to satisfy a specified requirement during the dynamic allocation period.