Console logger adds considerable latency to requests

[mikeharder]

The console logger adds considerable latency to requests. Here's a comparsion of the average and maximum latency with no logging, serilog to a file, and console logging:

Metric	No Logging	Serilog to File	Console Logging
Average (ms)	6.46	6.79	11.19
Max (ms)	7.08	8.45	67.63

https://github.com/mikeharder/AspNetLatency

A few options were discussed to improve console logging performance:

1. Don't block the request waiting for calls to Console.WriteLine() (or setting console colors). Queue writes to something faster like ConcurrentQueue, and use a background thread to remove from queue and call Console.WriteLine(). One downside is that log writes may appear out-of-order with respect to direct Console.WriteLine() calls. Another downside is the server process may end before all logs have been flushed from the queue.

2. Still write to the console synchronously during the request, but avoid expensive operations like setting colors. Could be an option on the existing console logger, or a new FastConsoleLogger.

[BrennanConroy]

@glennc Colors!

[BrennanConroy]

Just an FYI 1.0.0 doesn't have the ~35% perf improvement we added for Console Logging

[muratg]

There are a few issues that we're tracking specifically, e.g. #408

[BrennanConroy]

Tested with #536 and 1.2.0 Console Logger

Metric	No Logging	Serilog to File	Console Logging (1.2.0-*)	Background Console Logging
Average (ms)	3.347	3.517	4.606	3.2992
Max (ms)	5.1071	5.3236	12.5596	5.7356

[pakrym]

We are not expecting console to ever be quick enough per request logging in real world production applications.

We've moved actual console writing to a separate thread so it would be faster now but only until message queue is full (1000 messages) after that logger would start blocking again.