Method and apparatus for dynamic performance evaluation of data storage systems

• US 7,406,631 B2
• Filed: 10/02/2006
• Issued: 07/29/2008
• Est. Priority Date: 11/22/2002
• Status: Expired due to Fees

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Moore, Robert B
• Primary Examiner(s): DUNCAN, MARC M
• Application Number:
  US11/542,389
• Publication Number:
  US 20070028135A1
• Time in Patent Office: 666 Days
• Field of Search: None
• US Class Current: 714/47.1
• CPC Class Codes: G06F 11/3414 Workload generation, e.g. scripts, playback
• CPC Class Codes: G06F 11/3419 by assessing time
• CPC Class Codes: G06F 11/3485 for I/O devices
• CPC Class Codes: G06F 2201/81 Threshold
• CPC Class Codes: G06F 2201/88 Monitoring involving counting

Abstract

Improved approaches for evaluating performance of data storage systems used with computers are disclosed. The performance evaluation of the data storage systems utilizes dynamic performance evaluation by use of data throughput as a diagnostic. The data storage systems include, for example, either disk drives or RAIDs. In one embodiment, the invention identifies a sustained performance rate for a disk drive or RAID.

Claims

1. A method for evaluating performance of a RAID for streaming data, said method comprising:

(a) identifying a configured RAID including at least a plurality of disk drives for evaluation of its performance and certification as a RAID suitable for streaming data;

(b) evaluating data transfer performance of the plurality of the disk drives of the configured RAID by transferring a number of blocks from each of the plurality of disk drives;

(c) comparing, based on the evaluating of the data transfer performance of the plurality of the disk drives, the data transfer performance of the plurality of disk drives with minimum performance criteria required for certification of the RAID as suitable for streaming data; and

(d) certifying the configured RAID as suitable for streaming data when said comparing (c) indicates that the data transfer performance of the disk drives of the configured RAID exceeds the minimum performance criteria.

2. A method as recited in claim 1, wherein the data to be streamed has a media type, and wherein the minimum performance criteria is dependent on the media type to be streamed.

3. A method as recited in claim 2, wherein the media type is audio or video.

4. A method as recited in claim 1, wherein said evaluating (b) is performed separately on each of the disk drives of the configured RAID.

5. A method as recited in claim 4, wherein said comparing (c) compares the data transfer performance for each of the disk drives of the configured RAID with the minimum performance criteria, and

wherein said certifying (d) certifies the configured RAID only when the data transfer performance for each of the disk drives of the configured RAID exceeds the minimum performance criteria.

6. A method as recited in claim 1, wherein said identifying (a) comprises configuring a RAID including at least the plurality of disk drives.

7. A method as recited in claim 6, wherein the data to be streamed has a media type, and wherein the minimum performance criteria is dependent on the media type to be streamed.

8. A method as recited in claim 7, wherein the media type is audio or video.

9. A method as recited in claim 7, wherein said evaluating (b) is performed separately on each of the disk drives of the configured RAID.

10. A method as recited in claim 9, wherein said comparing (c) compares the data transfer performance for each of the disk drives of the configured RAID with the minimum performance criteria, and

wherein said certifying (d) certifies the configured RAID only when the data transfer performance for each of the disk drives of the configured RAID exceeds the minimum performance criteria.

11. A method for evaluating performance of a RAID that includes a plurality of disk drives for streaming data, said method comprising:

(a) producing an average transfer time for at least one of the disk drives;

(b) transferring a first number of data blocks from one of the disk drives;

(c) determining a measured transfer time for the time it takes for said transferring (b) to transfer the first number of data blocks from the at least one of the disk drives;

(d) determining whether the measured transfer time is substantially greater than the average transfer time;

(e1) increasing a performance error count when said determining (d) determines that the measured transfer time is substantially greater than the average transfer time, thereby evaluating the performance of the RAID based on the performance error count; and

(e2) certifying the RAID as suitable for streaming data when the performance error count is less than a maximum allowable error count for certification of the RAID as suitable for streaming data.

12. A method as recited in claim 11, wherein said method further comprises:

(f) repeating at least said transferring (b) through said increasing (e) for subsequent transfers of the first number of data blocks from the at least one of the disk drives.

13. A method as recited in claim 12, wherein said repeating (f) continues until all the data blocks of the at least one disk drive has undergone data transfer therefrom, and

wherein said method further comprises:

(g) comparing the performance error count with a maximum count; and

(h) determining whether the one of the disk drives has a deficient performance when the performance error count exceeds the maximum count.

14. A method as recited in claim 13, wherein said method further comprises:

(i) repeating said producing (a) through said determining (h) for each of the other of the disk drives of the RAID.

15. A method as recited in claim 14, wherein said method further comprises:

(j) determining that the RAID is inadequate to stream data when one or more of the disk drives of the RAID are determined to have a deficient performance.

16. A method as recited in claim 11, wherein said producing (a) is done empirically by measuring a transfer time over a sample size.

17. A method for evaluating performance of a disk drive, said method comprising:

(a) obtaining an average transfer time for the disk drive;

(b) transferring a first number of data blocks from the disk drive;

(c) determining a measured transfer time for the time it takes for said transferring (b) to transfer the first number of data blocks from the disk drive;

(d) determining whether the measured transfer time is substantially greater than the average transfer time;

(e1) increasing a performance error count when said determining (d) determines that the measured transfer time is substantially greater than the average transfer time, thereby evaluating the performance of the disk drive based on the performance error count; and

(e2) certifying the disk drive as suitable for streaming data when the performance error count is less than a maximum allowable error count for certification of the disk drive as suitable for streaming data.

18. A method as recited in claim 17, wherein said method further comprises:

(f) repeating at least said transferring (b) through said increasing (e) for subsequent transfers of the first number of data blocks from the disk drive.

19. A method as recited in claim 18, wherein said repeating (f) continues until all the data blocks of the disk drive have undergone data transfer therefrom, and

wherein said method further comprises:

(g) comparing the performance error count with a maximum count; and

(h) determining whether the disk drive has a deficient performance when the performance error count exceeds the maximum count.

20. A method as recited in claim 17, wherein said obtaining (a) is done empirically by measuring a transfer time over a sample size.

21. A method as recited in claim 17, wherein the performance of the disk drive being evaluated is a data throughput rate.

22. A server for streaming data, comprising:

a plurality of disk drives; and

a drive controller operatively connected to said disk drives, said drive controller controlling operation of said disk drives, obtaining data transfer time performance of each of said disk drives by transferring a number of blocks from each of the plurality of disk drives, comparing the data transfer time performance of each of said disk drives with minimum performance requirements, and certifying, based on the comparing of the data transfer time performance, suitability of said disk drives for use in streaming data when it is determined that the data transfer time performance of each of said disk drives meets or exceeds the minimum performance requirements.

23. A server as recited in claim 22, wherein said disk drives are configured into a RAID, and wherein said drive controller is a RAID controller.

24. A computer readable medium including at least computer program code for evaluating performance of a RAID that includes a plurality of disk drives for streaming data, said computer readable medium comprising:

computer program code for producing an average transfer time for at least one of the disk drives;

computer program code for transferring a first number of data blocks from one of the disk drives;

computer program code for determining a measured transfer time for the time it takes for the first number of data blocks to be transferred from the at least one of the disk drives;

computer program code for determining whether the measured transfer time is substantially greater than the average transfer time;

computer program code for increasing a performance error count when it is determined that the measured transfer time is substantially greater than the average transfer time, thereby evaluating the performance of the RAID based on the performance error count; and

computer program code for certifying the RAID as suitable for streaming data when the performance error count is less than a maximum allowable error count for certification of the RAID as suitable for streaming data.

25. A computer readable medium including computer program code for evaluating performance of a RAID for streaming data, comprising:

computer program code for identifying a configured RAID including at least a plurality of disk drives for evaluation of its performance and certification as a RAID suitable for streaming data;

computer program code for evaluating data transfer performance of the plurality of the disk drives of the configured RAID by transferring a number of blocks from each of the plurality of disk drives;

computer program code for comparing, based on the evaluating of the data transfer performance of the plurality of the disk drives, the data transfer performance of the plurality of disk drives with minimum performance criteria required for certification of the RAID as suitable for streaming data; and

computer program code for certifying the configured RAID as suitable for streaming data when said comparing (c) indicates that the data transfer performance of the disk drives of the configured RAID exceeds the minimum performance criteria.

26. A method for evaluating performance of a RAID that includes a plurality of disk drives for streaming data, said method comprising:

(a) producing an average transfer time for two or more of the plurality of disk drives;

(b) transferring a first number of data blocks from each one of the two or more of the plurality of disk drives;

(c) determining a measured transfer time for the time it takes for said transferring (b) to transfer the first number of data blocks from each one of the two or more of the plurality of disk drives;

(d) determining whether each one the measured transfer times is substantially greater than the average transfer time; and

(e) increasing a performance error count when said determining (d) determines that one of the measured transfer times is substantially greater than the average transfer time, thereby evaluating the performance of the RAID based on the performance error count.