July 19, 2012, 2:36 PM — Editors note: The following review is part of MacworldsGemFest 2012 series. Every weekday from mid June through mid August, the Macworld staff will use the Mac Gems blog to briefly cover a favorite free or low-cost program. Visit the Mac Gems homepage for a list of past Mac Gems.
Mac OS X does a lot behind the scenes, and it records many of its operations and errors in log files. You can access these log files through an included Mac utility called Console. Console logs can help you track down problems on your Mac, but Console offers a Spartan display, and its sorting options are limited.
Log Leech (Mac App Store link) steps in to remedy this. It reads these log files and presents them in a much more usable manner. The application can group log entries by application or process, something you can only do in Console by running searches. (Though Console lets you save log queries, which work like multi-criteria smart searches.) You can also sort by application name, date or number of entries; the latter lets you find which applications or processes have written the most log entries.
Log Leech lets you choose between viewing all system logs or Console Logs Only. As there has not been a console.log file in OS X for several versions, this latter option displays the results of the syslog -C command, which shows log entries that affect the current users account and applications. This is often useful when troubleshooting, to see what types of errors have occurred with applications you use. Double-clicking an entry shows all the log entries for that application or process.
This application is only an interface to system logs; it offers no tips on which log entries are worrisome. For example, the ath process has written 1,190 messages in the past week, yet these are not errors. This is not, of course, a limitation of Log Leech, but simply the fact that system logs contain lots of information that is hard to understand.
Console displays more than just system logs, and Log Leech might be more useful if it also could display logs stored in the users ~/Libary/Logs folder, or the system-level /Library/Logs folder. Some of these logs are simply installer logs, but some are crash logs or other diagnostic logs. While their information can be cryptic, they can at least help users know that there are problems with specific applications or services.