I haven't used this system extensively yet. But I don't really see how that situation gets improved by having a single-file configuration system.

First of all, if you have multiple processes trying to read/write the same config, that's kind of suspect, and if file I/O is a bottleneck for your config system, that's a different suspicious situation. Why are your processes writing to the config so... often?

But regardless, I can't see how those problems get immediately better by storing that config in a single file. If anything, having it split across multiple files would improve the situation, as different processes that might only be concerned with different sections of the config won't need to wait on file locks from process unrelated to their concerns.

I realize it may have sounded like I was suggesting the approach. Quite the contrary: I would never do that again or suggest it. I was merely pointing out that it was quite useful at times :-) We had lots of problems similar to what you were describing. Luckily that's all in the past now.