Huge memory and threads consumption about kafka4net

[thunderstumpges]

From what I recall of the design, and from a cursory look at the code, there is only ever one single thread per Producer that is in SendLoop() (each Producer instance has one sender thread). It is also normal for a producers send thread to wait on that event if there are no messages to send.

How many producers are being created by serilog-sinks-kafka? Can you verify the number of Producer instances? In general, you should share a single producer instance across the application (or at least major subsystem of the application). This may very well be an issue with serilog-sinks-kafka. We are using kafka4net heavily from IIS for logging many events, and see none of this issue.

[thunderstumpges]

a 5 minute look at serilog-sinks-kafka (I don't know serilog, or how many of these KafkaClient objects are created, but their method GetOrCreateKafkaProducerAsync does NOT perform double-check-locking and has a very possible race condition allowing many producers to be created.

https://github.com/wespday/serilog-sinks-kafka/blob/5b0d311fa3eb4e1d76a8a694cab99d9bed544d3f/src/Serilog.Sinks.Kafka/Sinks/Kafka/KafkaClient.cs#L98

[sungam3r]

Thank you for explanation! I will verify the number of Producer instances created by serilog-sinks-kafka.
And just for the sake of interest what about infinite wait timeout?

[sungam3r]

Yep, double-check-locking in serilog-sinks-kafka source code in GetOrCreateKafkaProducerAsync with some other minor modifications helped to solve this problem. Thank you again.

[thunderstumpges]

Great Glad to hear it.