Apparatus and method for adaptive logical partitioning of workfile disks for multiple concurrent mergesorts

• US 5,671,405 A
• Filed: 07/19/1995
• Issued: 09/23/1997
• Est. Priority Date: 07/19/1995
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Wu, Kun-Lung, Yu, Philip Shi-Lung
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): ROBINSON, GRETA LEE
• Application Number:
  US08/504,160
• Time in Patent Office: 797 Days
• Field of Search: 395/600, 395/607, 395/601, 395/200.03, 395/456
• US Class Current: 1/1
• CPC Class Codes: G06F 7/36 Combined merging and sorting

Abstract

System and method for improving response time of concurrent mergesort operations in an information handling system, which includes one or more logical processors each operating under control of an image of an operating system program, a database storage system for storing data in a predetermined data structure, one or more workfile storage devices for storing workfiles during mergesort operations, means for sorting the data structure into one or more ordered runs, means for determining a logical partition size for the workfile storage devices, means for selecting a least loaded partition, means for writing the ordered runs in the selected partition in the workfile storage devices, and means for merging the ordered runs into a single sorted run.

Claims

1. An information handling system for improving response time of multiple, concurrent mergesort operations, comprising:

a plurality of logical processors each operating under control of an image of an operating system program;

a database storage system for storing data in a predetermined data structure;

one or more workfile storage devices for storing workfiles during mergesort operations;

means for sharing one or more of said workfile storage devices by one or more of said logical processors; and

means for executing a plurality of mergesort operations, wherein each mergesort operation is executed on a separate logical processor and wherein said means for executing each mergesort operation comprises;

means for sorting said data structure into one or more ordered runs;

means for determining a logical partition size for said workfile storage devices;

means for selecting a least loaded partition;

means for writing said one or more ordered runs into said workfile storage devices in said selected partition; and

means for merging said one or more ordered runs into a single sorted run.

2. An information handling system for improving response time of concurrent mergesort operations, according to claim 1, further comprising:

means for partitioning said workfile storage devices into one or more groups.

3. An information handling system for improving response time of concurrent mergesort operations, according to claim 1, wherein said means for determining a logical partition size further comprises:

means for dynamically modifying said logical partition size based on system workload characteristics.

4. An information handling system for improving response time of concurrent mergesort operations, according to claim 3, wherein said system workload characteristics comprise an indicator of average utilization of said workfile storage devices.

5. An information handling system for improving response time of concurrent mergesort operations, according to claim 1, further comprising:

means for managing a plurality of concurrent mergesort requests.

6. A method for improving response time of multiple, concurrent mergesort operations, in an information handling system having a database storage system with a predetermined data structure, comprising the steps of:

providing a plurality of logical processors each operating under control of an image of an operating system program;

providing one or more workfile storage devices for storing workfiles during mergesort operations;

sharing one or more of said workfile storage devices by one or more of said logical processors; and

executing a plurality of mergesort operations, wherein each mergesort operation is executed on a separate logical processor and wherein, for each mergesort operation, said executing comprises the steps of;

sorting said data structure into one or more ordered runs;

determining a logical partition size for said workfile storage devices;

selecting a least loaded partition;

writing said one or more ordered runs into said workfile storage devices in said selected partition; and

merging said one or more ordered runs into a single sorted run.

7. A method for improving response time of concurrent mergesort operations, according to claim 6, further comprising the step of:

partitioning said workfile storage devices into one or more groups.

8. A method for improving response time of concurrent mergesort operations, according to claim 6, further comprising the step of:

dynamically modifying said logical partition size based on system workload characteristics.

9. A method for improving response time of concurrent mergesort operations, according to claim 8, wherein said system workload characteristics comprise an indicator of average utilization of said workfile storage devices.

10. A method for improving response time of concurrent mergesort operations, according to claim 6, further comprising the step of:

managing a plurality of concurrent mergesort requests.