What do you log in your desktop applications to improve stability?

问题

I've started using SmartInspect in my Delphi applications because my users were running into bugs/problems I couldn't reproduce on my machine. When I have a general idea of the problem I'll monitor the application in a few specific places to confirm what is or is not working.

When the bug doesn't have an obvious cause, I feel lost. I don't know where to start logging in order to narrow down the problem. Are there common techniques or best practices for using a logger?

SmartInspect seems to be quite powerful, but I don't know quite what to log or how to organise my logs so the data is meaningful and useful for catching bugs.

NOTE: I'm using SmartInspect but I assume the answers should be suitable for any logging package.

回答1:

Here are some guidelines I tried to implement in my own OpenSource logging unit, but it's fairly generic, and as you state, it should be suitable for any logging package:

Make several levels (we use sets) of logging, to tune the logging information needed;
Log all exceptions, even the handled one with a try...except block - and add an exception classes list not worth logging (e.g. EConvertError) - e.g. our unit is able to log all exceptions via a global exception "hook" (no try..except to add in your code), and handle a list of exception classes to be ignored;
Log all "fatal" errors, like database connection issues, or wrong SQL syntax - should be done though "log all exceptions" previous item;
For such exceptions, log the stack trace to know about the calling context;
Be able to log all SQL statements, or database access;
Add a generic User Interface logging, to know which main functions of the software the User did trigger (e.g. for every toolbar button or menu items): it's very common that the user said 'I have this on my screen/report, but I didn't do anything'... and when you see the log, you will discover that the "anything" was done. ;)
Monitor the main methods of your application, and associated parameters;
Logging is an evolving feature: use those general rules above, then tune your logging from experiment, according to your debugging needs.

回答2:

For UI-driven applications here are the main things I instrument first:

ActionManager or ActionList's events when an action executes (gives me a user clicked here then here then here list).
Unhandled Exceptions with tracebacks using JCL debug go right in my main log, whereas if I was using MadExcept or EurekaLog, exceptions have their own log.
Background thread starts, stops and significant history events
Warnings, errors, API function failures, file access failures, handled (caught) exceptions.

回答3:

Current memory usage can be useful for long running processes to see if there are memory leaks (which could lead to an out of memory error some day).

来源：https://stackoverflow.com/questions/6728879/what-do-you-log-in-your-desktop-applications-to-improve-stability

标签

Delphi

logging

desktop-application