Cached is 7.135E-6 seconds each call, uncached is 2.555E-5 seconds each. At 100 requests per second that is .7ms vs. 2.5ms. That's probably not too significant.

In a socket server with filesystem logging, I/O is apt to be the real bottleneck. Threading would be useful. For thread safety, you need the :locked attribute set on &cache_strftime to prevent a race condition.

After Compline,
Zaxo