Systems and methods for load balancing across media server instances
A system is presented for load balancing across media server instances. In an embodiment, media is broken out into a multi-tenanted service allowing the media to be scaled independently of the number of organizations supported on a cloud-based collaboration platform. Scaling may occur in a scaling-out or a scaling-in operation. States for a media service may comprise in-service, quiescing, quiesced, failed, etc. The states may be used to monitor sessions associated with an instance and determine which media instances to terminate during a scaling-in operation. In an embodiment, new instances may be added to a collection of media instances in response to an increased workload in a scaling-out operation.
1. A system for load balancing a workload across a dynamically resized collection of computing resources providing long running services in a system for handling a media request, the system comprising:
a processor; and
a memory, wherein the memory stores instructions that, when executed by the processor, cause the processor to:
receive, by a media manager, a request for a resource;
select an instance of a group of instances, by a datastore operatively coupled to the media manager, wherein the instance meets a criteria, and refraining from selecting any instance of the group of instances that meets an other criteria, each instance of the group being configured to maintain a collection of sessions associated with the instance meeting the criteria by:
in response to being forwarded the request, adding a session associated with the request to the collection of sessions; and
in response to an instance state change, removing the session from the collection of sessions;
detect, by the media manager, a scaling-in operation within a sub-group of instances meeting the criteria;
transition at least one instance of the sub-group of instances meeting the criteria to a sub-group of instances meeting the other criteria;
maintain each instance of the sub-group of instances meeting the other criteria while the collection of sessions associated with the instance meeting the other criteria comprises at least one session; and
transition the instance meeting the other criteria to a sub-group of instances when the collection of sessions associated with the instance meeting the other criteria is empty.
2. The system of claim 1 , wherein the instance meeting the criteria comprises an in-service instance.
3. The system of claim 1 , wherein the instance meeting the other criteria comprises a quiescing instance.
4. The system of claim 1 , wherein the sub-group of instances comprise quiesced instances.
5. The system of claim 1 , further comprising terminating instances in the sub-group of instances.
6. The system of claim 5 , wherein the termination is performed by one of: the instance itself directly or through a third-party process.
7. The system of claim 3 , wherein the quiescing instance is in an indefinite state.
8. The system of claim 6 , wherein the quiescing instance is in a state that ends after a pre-determined interval of time.
9. The system of claim 7 , wherein the quiescing state is ended by an explicit stimulus.
10. The system of claim 9 , wherein the explicit stimulus comprises at least one of: session ending, disconnection, resource expiration, and time expiration.
11. The system of claim 1 , wherein an instance is selected based on the load metrics associated with the instances in the datastore.
12. The system of claim 11 , wherein the memory stores instructions that, when executed by the processor, cause the processor to further:
determine that the load metric satisfies a threshold;
determine that the sub-group of instances meeting the other criteria comprises at least one instance; and
transition at least one instance from the sub-group of instances meeting the other criteria to the sub-group of instances meeting the criteria.
13. The system of claim 1 , wherein the workload comprises real-time media streams of indeterminate duration.
14. The system of claim 13 , wherein media in the media streams comprise at least one of: email, vmail, chat, video, text-messaging, web, social media, and co-browsing.
15. The system of claim 1 , wherein the instance state change comprises a comparison by the media manager of a current state with a prior state of the instance.
16. The system of claim 1 , wherein the detected scaling-in operation comprises a load condition which satisfies a scaling-in threshold.
17. The system of claim 16 , wherein the detecting of the satisfied load condition is performed by a monitoring service which monitors computing load.
18. The system of claim 17 , wherein the monitoring service is a third-party service.
19. The system of claim 1 , wherein the transitioning is performed by the instance itself.