System and method for detecting imbalances in dynamic workload scheduling in clustered environments

• US 20070016687A1
• Filed: 07/14/2005
• Published: 01/18/2007
• Est. Priority Date: 07/14/2005
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Gupta, Manish, Mann, Vijay, Anerousis, Nikolaos, Ghosal, Sugata, Mummert, Lily, Agarwal, Manoj
• Application Number:
  US11/181,352
• Publication Number:
  US 20070016687A1
• Time in Patent Office: Days
• US Class Current: 709/238
• CPC Class Codes: G06F 9/5083 Techniques for rebalancing the load in a distributed system

Abstract

Methods, systems and computer program products for detecting a workload imbalance in a dynamically scheduled cluster of computer servers are disclosed. One such method comprises the steps of monitoring a plurality of metrics at each of the computer servers, detecting change points in the plurality of metrics, generating alarm points based on the detected change points, correlating the alarm points and identifying, based on an outcome of the correlation, one or more of the computer servers causing a workload imbalance. Systems and computer program products for practicing the above method are also disclosed.

Claims

1. A method for detecting a workload imbalance in a dynamically scheduled cluster of computer servers, said method comprising:

monitoring a plurality of metrics at each of said computer servers;

detecting change points in said plurality of metrics;

generating alarm points based on detected change points;

correlating said alarm points; and

identifying, based on an outcome of said correlating, one or more of said computer servers causing said workload imbalance.

2. The method of claim 1, wherein said metrics comprise end-to-end system metrics.

3. The method of claim 1, wherein said step of monitoring a plurality of metrics at each of said computer servers comprises:

sampling, at periodic intervals, cumulative response times of requests at each of said computer servers; and

sampling, at periodic intervals, routing weights dynamically assigned to each of said computer servers.

4. The method of claim 1, further comprising:

generating time series data representative of response times for said computer servers to respond to requests; and

generating time series data representative of routing weights that are dynamically assigned to said computer servers.

5. The method of claim 4, further comprising:

detecting a change point in said time series data representative of response times that is decreasing; and

detecting a change point in said times series data representative of routing weights that is increasing.

6. The method of claim 5, further comprising:

filtering said alarm points.

7. The method of claim 6, wherein said alarm points are correlated in a defined time window.

8. The method of claim 1, further comprising:

probing said computer servers to determine whether said computer servers are functioning correctly.

9. The method of claim 1, further comprising notifying a system administrator of occurrence of a Storm Drain condition.

10. The method of claim 9, further comprising at least one of:

stopping routing/scheduling of requests to at least one identified computer server;

quiescing at least one identified computer server; and

rejuvenating at least one identified computer server.

11. A system for detecting a workload imbalance in a dynamically scheduled cluster of computer servers, said system comprising:

a plurality of sensors adapted to monitor a plurality of metrics at each of said computer servers;

a change point detector adapted to detect changes in said plurality of metrics and generate alarm points based on detected changes;

a correlation engine adapted to correlate said alarm points generated from said plurality of metrics and identify, based on an outcome of correlation of said alarm points, one or more of said computer servers causing said workload imbalance.

12. The system of claim 11, wherein said plurality of sensors are adapted to:

sample, at periodic intervals, cumulative response times of requests at each of said computer servers; and

sample, at periodic intervals, routing weights dynamically assigned to each of said computer servers.

13. The system of claim 11, wherein said plurality of sensors are adapted to:

generate time series data representative of response time for said computer servers to respond to requests; and

generate time series data representative of routing weights that are dynamically assigned to said computer servers.

14. The system of claim 13, wherein said change point detector is adapted to:

identify a change point in said time series data representative of response times that is decreasing; and

identify a change point in said times series data representative of routing weights that is increasing.

15. The system of claim 11, further comprising filters adapted to filter said alarm points.

16. The system of claim 15, further comprising a policy repository adapted to store filtering rules for validating said alarm points using said filters.

17. The system of claim 11, further comprising a Reaction Manager adapted to notify an authority of a detected Storm Drain condition.

18. The system of claim 17, wherein said Reaction Manager is adapted to perform at least one of:

stop routing/scheduling of requests to at least one identified computer server;

quiesce at least one identified computer server; and

rejuvenate at least one identified computer server server(s).

19. A system for detecting a workload imbalance in a dynamically scheduled cluster of computer servers, said system comprising:

a memory unit adapted to store data and instructions to be performed by a processing unit; and

a processing unit coupled to said memory unit, said processing unit being programmed to;

monitor a plurality of metrics at each of said computer servers;

detect change points in said plurality of metrics;

generate alarm points based on said detected change points;

correlate said alarm points; and

identify, based on an outcome of said correlation, one or more of said computer servers causing a workload imbalance.

20-22. -22. (canceled)

23. A computer program product comprising a computer readable medium tangibly embodying a computer program recorded therein for performing a method of detecting a workload imbalance in a dynamically scheduled cluster of computer servers, said method comprising:

monitoring a plurality of metrics at each of said computer servers;

detecting change points in said plurality of metrics;

generating alarm points based on detected change points;

correlating said alarm points; and

identifying, based on an outcome of said correlating, one or more of said computer servers causing said workload imbalance.

24-26. -26. (canceled)