spdlog: Fast C++ logging library
Just announced:
spdlog: Super fast C++ logging library [GitHub]
The description is really "in a nut":
Very fast, header only, C++ logging library.
Install: Just copy the files to your build tree and use a C++11 compiler
Features:
- Very fast -- performance is the primary goal (see becnhmarks below)
- Headers only
- No dependencies
- Cross platform - Linux / Windows on 32/64 bits
- Mult/Single threaded loggers
- Rotating log files
- Daily log files
- Console logging
- Optional async logging
- Logging levels
- Custom formatting with user defined patterns


A nice tutorial on a feature that leads to convenient and safe calling code:
The STE||AR Group has released V0.9.9 of HPX -- A general purpose parallel C++ runtime system for applications of any scale.