To meet the requirements of enriching logging with more context and improving throughput while reducing latency, the customer should use an asynchronous logging approach. Here's why option B is correct:

Async Logger: Asynchronous logging helps in improving the performance by decoupling the logging from the main thread of execution. This reduces the latency of message processing since logging operations are offloaded to a separate thread.

Logging Level Greater than INFO: Logging at levels such as WARN, ERROR, or FATAL ensures that only essential logs are written asynchronously, further enhancing performance. Avoiding DEBUG or TRACE levels unless necessary reduces the overhead of logging.

Pattern Layout with [%MDC]: Using the pattern layout with [%MDC] in the log4j2.xml configuration file allows the inclusion of mapped diagnostic context in the logs. MDC is a feature that provides context-specific information, such as transaction IDs or user IDs, which helps in tracing and debugging.

Example configuration in log4j2.xml:

This configuration ensures that the logs are enriched with context information provided by MDC and processed asynchronously to maintain high throughput and low latency.

References

Log4j2 Asynchronous Logging

Mapped Diagnostic Context (MDC) in Log4j2