Pantheios is a good candidate in term of perormance but my personal preference is P7 library.
My internal tests (CPU i7-4870HQ, SSD) shows that P7 is faster than Pantheios.
- Pantheios writes 1.8M logs lines per second (time & text message)
- P7 writes 2.4M logs lines per second (time, thread, CPU core, function, file, line and text message)
