Method for storing long-term performance data in a computer system with finite storage space

1. A method for systematically monitoring and recording performance information in a computer system, comprising:

periodically measuring a number of performance parameters in the computer system;

storing data representing values for the measured performance parameters in a long-term storage space;

recurrently compressing data stored in the long-term storage space, thereby allowing additional data representing newly collected performance information to be stored in the long-term storage space;

assigning a short-term storage space for storing real-time data carrying performance information of the computer system; and

periodically consolidating the real-time data stored in the short-term storage space and storing the consolidated real-time data in the long-term storage space.

2. The method of claim 1 , wherein recurrently compressing the data stored in the long-term storage space involves compressing the stored data when utilization of the long-term storage space exceeds a threshold.

3. The method of claim 1 , wherein compressing the data stored in the long-term storage space involves replacing a set of existing data points with fewer new data points which preserve certain characteristics of the replaced data points.

4. The method of claim 3 , wherein replacing the existing data points stored in the long-term storage space with fewer new data points involves:

computing an average value for every two successive existing data points stored in the long-term storage space; and

replacing every two successive existing data points with a new data point whose value is the average of the two data points being replaced.

5. The method of claim 1 , wherein consolidating the real-time data involves compressing the real-time data with the same compression ratio with which the data stored in the long-term storage space has been compressed.

6. The method of claim 5 , wherein compressing the real-time data involves replacing every 2 n real-time data points with one new data point whose value is the average of the 2 n real-time data points, and wherein n is the number of times the data stored in the long-term storage space has been compressed.

7. A computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for systematically monitoring and recording performance information in a computer system, the method comprising:

periodically measuring a number of performance parameters in the computer system;

storing data representing values for the measured performance parameters in a long-term storage space;

recurrently compressing data stored in the long-term storage space, thereby allowing additional data representing newly collected performance information to be stored in the long-term storage space;

assigning a short-term storage space for storing real-time data carrying performance information of the computer system; and

periodically consolidating the real-time data stored in the short-term storage space and storing the consolidated real-time data in the long-term storage space.

8. The computer-readable storage medium of claim 7 , wherein recurrently compressing the data stored in the long-term storage space involves compressing the stored data when utilization of the long-term storage space exceeds a threshold.

9. The computer-readable storage medium of claim 7 , wherein compressing the data stored in the long-term storage space involves replacing a set of existing data points with fewer new data points which preserve certain characteristics of the replaced data points.

10. The computer-readable storage medium of claim 9 , wherein replacing the existing data points stored in the long-term storage space with fewer new data points involves:

computing an average value for every two successive existing data points stored in the long-term storage space; and

replacing every two successive existing data points with a new data point whose value is the average of the two data points being replaced.

11. The computer-readable storage medium of claim 7 , wherein consolidating the real-time data involves compressing the real-time data with the same compression ratio with which the data stored in the long-term storage space has been compressed.

12. The computer-readable storage medium of claim 11 , wherein compressing the real-time data involves replacing every 2 n real-time data points with one new data point whose value is the average of the 2 n real-time data points, and wherein n is the number of times the data stored in the long-term storage space has been compressed.

13. An apparatus for systematically monitoring and recording performance information in a computer system, comprising:

a monitoring mechanism configured to periodically monitor a number of performance parameters in the computer system;

a data storage mechanism configured to store data representing values for the measured performance parameters in a long-term storage space, further comprising a short-term storage space for storing real-time data carrying performance information of the computer system; and

a compression mechanism configured to recurrently compress data stored in the long-term storage space, thereby allowing additional data representing newly collected performance information to be stored in the long-term storage space.

14. The apparatus of claim 13 , wherein while recurrently compressing the data stored in the long-term storage space, the compression mechanism is configured to compress the stored data when utilization of the long-term storage space exceeds a threshold.

15. The apparatus of claim 13 , wherein while compressing the data stored in the long-term storage space, the compression mechanism is configured to replace a set of existing data points with fewer new data points which preserve certain characteristics of the replaced data points.

16. The apparatus of claim 15 , wherein while replacing the existing data points stored in the long-term storage space with fewer new data points, the compression mechanism is configured to:

compute an average value for every two successive existing data points stored in the long-term storage space; and

to replace every two successive existing data points with a new data point whose value is the average of the two data points being replaced.

17. The apparatus of claim 13 , wherein while consolidating the real-time data, the consolidation mechanism is configured to compress the real-time data with the same compression ratio with which the data stored in the long-term storage space has been compressed.