Stephan Menzel wrote today on the Boost developer mailing list (see here):
Lacking boost.log we created or own logging class which is basically an as-simple-as-possible Syslog client. (I like to process and accumulate there). It used to be boost.format to assemble the messages which proved slower than log4cxx. With Spirit 2.1 in 1.41 however we changed to use a Karma message generator for this purpose which improved speed dramatically.
Thanks Stephan! We are happy to hear that!
If you have other success stories while using Spirit, we would love to hear about your experience. Just leave a comment below, we happily will write about it.