fast and flexible logger

 Log::Fast is very fast logger, designed for use in applications with thousands
 high-level events/operations per second (like network servers with thousands
 clients or web spiders which download hundreds url per second).
 .
 For example, on Core2Duo sending about 5000 messages to log on enabled log
 levels or 20000 messages on disabled log levels in one second will slow down
 your application only by 2-3%.
 .
 Comparing to some other CPAN modules, this one (in average): faster than
 Log::Dispatch in about 45 times, faster than Log::Handler in about 15 times,
 faster than Sys::Syslog in about 7 times, and slower than Log::Syslog::Fast in
 about 2 times.
 .
 Features:
 .
  * Global and local logger objects
  * Output to any open filehandle or local syslog
  * 5 log levels: ERR, WARN, NOTICE, INFO, DEBUG
  * Configurable prefix (log level, date/time, caller function name)
  * sprintf() support
  * Unicode support (UTF8)
  * Can avoid calculating log message content on disabled log levels