Event overflow handling by coalescing and updating previously-queued event notification

摘要

An event notification method for distributed processing systems provides reduction of queue space and event processing bandwidth associated with duplicate events such as a particular event that is duplicated and results in multiple event notifications propagated for multiple consumers. When a duplicate event notification is received at an input to an event notification queue, rather than queuing the duplicate event notification, a sequence number of the event notification already in the queue is updated to indicate to the event consumer, exactly how many duplicate events have been received. The timestamp of the updated event notification may also be set to the timestamp of the most recently received duplicate event notification.

主权项

1. A method for event notification within a computer system processing cluster comprising a plurality of physical or virtual processing modes, the method comprising:
receiving event notifications corresponding to events occurring on one or more of the processing nodes; queuing the received event notifications in one or more queues for delivery to event consumers; coalescing duplicate event notifications in a single resulting event notification, wherein the event notifications contain a event sequence number stored therein, wherein the coalescing further increments the event sequence number by modifying the event sequence number stored in the single resulting event notification to yield a modified event notification that, when provided to one of the event consumers indicates to the one of the event consumers, a total number of original and duplicate events that have been received, and wherein the coalescing further modifies a timestamp stored in the single resulting event notification to match a timestamp stored in a most recent one of the duplicate event notifications, by reading the timestamp of the most recent one of the duplicate event notifications and writing a value of the timestamp of the most recent one of the duplicate event notifications to a storage location of the timestamp stored in the single resulting event notification; and at the event consumer, determining whether the event notifications have been duplicated one or more times by reading the event sequence number stored in the event notifications to determine whether the event notifications have been modified to indicate the total number of original and duplicate events that have been received.