DISTRIBUTED DEMAND-BASED STORAGE QUALITY OF SERVICE MANAGEMENT USING RESOURCE POOLING

• US 20130326064A1
• Filed: 05/31/2012
• Published: 12/05/2013
• Est. Priority Date: 05/31/2012
• Status: Active Grant

• Current Assignee: Vmware LLC (Broadcom, Inc.)
• Original Assignee: VMware, Inc. (Broadcom, Inc.)
• Inventors: Gulati, Ajay, Shanmuganathan, Ganesha, Varman, Peter Joseph
• Granted Patent: US 9,244,742 B2
• Time in Patent Office: Days
• US Class Current: 709/226
• CPC Class Codes: G06F 2009/45575 Starting, stopping, suspending or resuming virtual machine instances
• CPC Class Codes: G06F 2009/45579 I/O management, e.g. providing access to device drivers or storage
• CPC Class Codes: G06F 9/45533 Hypervisors; Virtual machine monitors
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects
• CPC Class Codes: G06F 9/4881 Scheduling strategies for dispatcher, e.g. round robin, multi-level priority queues
• CPC Class Codes: G06F 9/5061 Partitioning or combining of resources
• CPC Class Codes: H04L 47/805 QOS or priority aware

Abstract

A system and method for providing quality of service (QoS) for clients running on host computers to access a common resource uses a resource pool module and a local scheduler in at least one of the host computers. The resource pool module operates to compute an entitlement of each client for the common resource based on a current capacity for the common resource and demands of the clients for the common resource. In addition, the resource pool module operates to assign a portion of the computed current capacity for the common resource to a particular host computer using the computed entitlement of each client running on the particular host computer. The local scheduler operates to allocate the portion of the computed current capacity among the clients running on the particular host computer.

Claims

1. A method for providing quality of service (QoS) for clients running on host computers to access a common resource, the method comprising:

computing a current capacity for the common resource based a global average latency for accessing the common resource by the clients;

computing an entitlement of each client for the common resource based on the computed current capacity and demands of the clients for the common resource;

assigning a portion of the computed current capacity for the common resource to a particular host computer using the computed entitlement of each client running on the particular host computer; and

allocating the portion of the computed current capacity among the clients running on the particular host computer.

2. The method of claim 1, wherein the computing the entitlement of each client includes distributing the computed current capacity for the common resource among the clients based on at least one QoS parameter set for each of the clients.

3. The method of claim 2, wherein the distributing the computed current capacity for the common resource includes temporarily limiting the amount of the computed current capacity distributed to a client to the computed entitlement for that client.

4. The method of claim 2, wherein the distributing the computed current capacity for the common resource includes distributing the computed current capacity for the common resource among the clients based on shares assigned to the clients.

5. The method of claim 1, further comprising distributing a global reservation value for the common resource among the clients to derive dynamic reservation values for the clients, including temporarily limiting the amount of the computed current capacity distributed to a client to the computed entitlement for that client, wherein the dynamic reservation values of the clients are used for the allocating the portion of the computed current capacity among the clients running on the particular host computer.

6. The method of claim 5, wherein the distributing the global reservation value for the common resource among the clients includes distributing the global reservation value through a hierarchical structure of parent and child nodes such that the global reservation value at a root node of the hierarchical structure is distributed to lower nodes of the hierarchical structure in a level-by-level process.

7. The method of claim 1, further comprising computing the demand of each client running on a particular host computer using a local average latency for accessing the common resource from the particular host computer and an average number of inputs/outputs in response requests to access the common resource from that client.

8. The method of claim 7, further comprising storing the computed demand in a shared file that is accessible by each of the host computers or transmitting the computed demand to other host computers in connection with the particular host computer.

9. The method of claim 1, wherein the assigning the portion of the computed current capacity for the common resource to the particular host computer includes adjusting the depth of a host queue of the particular host computer, the host queue being used to store outstanding requests for the common resource from the clients running on the particular host computer.

10. The method of claim 1, wherein the computing the current capacity for the common resource includes computing the current capacity for the common resource using the global average latency, a smoothing parameter and a resource congestion threshold value.

11. A system comprising:

at least one processor;

a plurality of clients operably connected to the at least one processor;

a resource interface with a host queue to store requests from the clients to access a common resource;

a resource pool module operably connected to the at least one processor, the resource pool module comprising;

a first component configured to compute a current capacity for the common resource based a global average latency for accessing the common resource by the clients;

a second component configured to compute an entitlement of each client for the common resource based on the computed current capacity and demands of the clients for the common resource; and

a third component configured to assign a portion of the computed current capacity for the common resource to a host computer using the computed entitlement of each client; and

a scheduler operably connected to the resource pool module, the schedule being configured to allocate the portion of the computed current capacity among the at least one client running on the host computer.

12. The system of claim 11, wherein the resource pool module is configured to distribute the computed current capacity for the common resource among the clients based on at least one QoS parameter set for each of the clients to compute the entitlement of each client for the common resource.

13. The system of claim 12, wherein the resource pool module is configured to temporarily limit the amount of the computed current capacity distributed to a client to the computed entitlement for that client to compute the entitlement of each client for the common resource.

14. The system of claim 12, wherein the resource pool module is configured to distribute the computed current capacity for the common resource among the clients based on shares assigned to the clients.

15. The system of claim 11, wherein the resource pool is configured to distribute a global reservation value for the common resource among the clients to derive dynamic reservation values for the clients, wherein the resource pool is further configured to temporarily limit the amount of the computed current capacity distributed to a client to the computed entitlement for that client, and wherein the dynamic reservation values of the clients are used to allocate the portion of the computed current capacity among the clients.

16. The system of claim 15, wherein the resource pool module is configured to distribute the global reservation value through a hierarchical structure of parent and child nodes such that the global reservation value at a root node of the hierarchical structure is distributed to lower nodes of the hierarchical structure in a level-by-level process.

17. The system of claim 11, wherein the resource pool module is configured to compute the demand of each client using a local average latency for accessing the common resource from the host computer and an average number of inputs/outputs in response requests to access the common resource from that client.

18. The system of claim 17, wherein the resource pool module is further configured to store the computed demand in a shared file that is accessible by other host computers or configured to transmit the computed demand to other host computers in connection with the host computer.

19. The system of claim 11, wherein the resource pool module is configured to adjust the depth of a host queue of the host computer to assign the portion of the computed current capacity for the common resource to the host computer, the host queue being used to store outstanding requests for the common resource from the clients.

20. The system of claim 11, wherein the resource pool module is configured to compute the current capacity for the common resource using the global average latency, a smoothing parameter and a resource congestion threshold value.

21. A computer-readable storage medium containing program instructions for providing quality of service to clients in host computers to access a common resource, wherein execution of the program instructions by one or more processors of the host computers the one or more processors causes the one or more processors to perform steps comprising:

computing a current capacity for the common resource based a global average latency for accessing the common resource by the clients;

computing an entitlement of each client for the common resource based on the computed current capacity and demands of the clients for the common resource;

assigning a portion of the computed current capacity for the common resource to a particular host computer using the computed entitlement of each client running on the particular host computer; and

allocating the portion of the computed current capacity among the clients running on the particular host computer.

22. The computer-readable storage medium of claim 21, wherein the computing the entitlement of each client includes distributing the computed current capacity for the common resource among the clients based on at least one QoS parameter set for each of the clients.

23. The computer-readable storage medium of claim 22, wherein the distributing the computed current capacity for the common resource includes temporarily limiting the amount of the computed current capacity distributed to a client to the computed entitlement for that client.

24. The computer-readable storage medium of claim 22, wherein the distributing the computed current capacity for the common resource includes distributing the computed current capacity for the common resource among the clients based on shares assigned to the clients.

25. The computer-readable storage medium of claim 21, wherein the steps further comprises distributing a global reservation value for the common resource among the clients to derive dynamic reservation values for the clients, including temporarily limiting the amount of the computed current capacity distributed to a client to the computed entitlement for that client, wherein the dynamic reservation values of the clients are used for the allocating the portion of the computed current capacity among the clients running on the particular host computer.

26. The computer-readable storage medium of claim 25, wherein the distributing the global reservation value for the common resource among the clients includes distributing the global reservation value through a hierarchical structure of parent and child nodes such that the global reservation value at a root node of the hierarchical structure is distributed to lower nodes of the hierarchical structure in a level-by-level process.

27. The computer-readable storage medium of claim 21, wherein the steps further comprises computing the demand of each client running on a particular host computer using a local average latency for accessing the common resource from the particular host computer and an average number of inputs/outputs in response requests to access the common resource from that client.

28. The computer-readable storage medium of claim 21, wherein the steps further comprises the computed demand in a shared file that is accessible by each of the host computers.

29. The computer-readable storage medium of claim 21, wherein the assigning the portion of the computed current capacity for the common resource to the particular host computer includes adjusting the depth of a host queue of the particular host computer, the host queue being used to store outstanding requests for the common resource from the clients running on the particular host computer.

30. The computer-readable storage medium of claim 21, wherein the computing the current capacity for the common resource includes computing the current capacity for the common resource using the global average latency, a smoothing parameter and a resource congestion threshold value.