Hiya,
Just writing this blog intending to help & investigate Azure Event Hubs delays issues as the scope these kind of issues are very wide & complex.
If you are facing any delays in receiving events from Azure Events Hubs then below are possible causes:
A) Network latency:
If there is a network issue that causes a delay in the transmission of events from the event hub to the consumer, this could cause a delay in delivery. You can troubleshoot using PsPing or tcpPing related tools.
B)Processing backlog:
If the consumer is unable to process events as quickly as they are being received, this can cause a backlog that results in a delay in delivery. If you do not find any information from client side Microsoft can help you on this matter.
C)Consumer application malfunction or performance issues:
If the consumer application is not functioning properly, this can cause a delay in processing and delivery of events. Please monitor your consumer applications & where its hosted machine's CPU/Memory or any related performance issues.
D)Partition leasing:
If the consumer is using a partition leasing mechanism and the lease has expired, this can cause a delay in delivery of events until the consumer re-establishes its lease.
E)Service upgrades:
If there is an issue with the Azure Event Hub backend service, this can cause a delay in delivery of events. Microsoft support can help you here to exactly find out issues from Azure backends.
F)Event ordering:
If the consumer requires events to be processed in a specific order, this can cause a delay in delivery if events are not being received in that order.
G)Storage latency:
If storage account used for checkpointing is having some latencies or issues from backend then this can also cause delays. Again if you do not find out any information from your diagnostics logs then Microsoft support can help you here.
Hope this information helps.
Thank you.
Cheers,
Ani
