26 March 2008

Log level philosophy

The level of severity at which you log a particular line probably doesnt get a great deal of attention. Points of contention are probably whether something is an error or warning, or whether it is an info or debug. Here Alex Miller discusses his thoughts on the subject.

Some comments on the article:

"DEBUG should be used only during development for debugging."... I've seen a lot of systems that always run in debug.

The article doesnt discuss fatal errors, I use this level of logging as a way of deciding that the log line should be sent to a support team as an email or sms. Although a more powerful solution is a system that watches log files and allows certain (regex) patterns to be matched against each log line, with rules kicking in deciding what should be done, e.g. send sms, stop system etc.

Also I do get fustrated when I see logging that doesnt include much detail, e.g. "Failed to submit order"... how about logging the details of the order too, this helps debugging and log forensics no end.