I spent a lot of time trying to build a fast logging system in my last couple of jobs. The basic lesson (and I'm only talking about C/C++/C# here) is that you will spend most of your time formatting strings if you do your file I/O asynchronously.
Since this system has a preprocessor mode, I assume they learnt the same lesson.
The bigger lesson is that it really doesn't matter how many millions of logs you can generate per second if you don't have the infrastructure to store and analyze them easily. No one is going to enjoy digging through these things and the more you generate, the harder it is to extract meaningful information.
In other words, pay a lot more attention to what you'll do with the logs rather than how fast you can spew them out. I have rarely needed more than a few thousand log messages/sec even for a loaded MMO server. I spent way more time creating ways to look at these logs and making them accessible in near real time.
Since this system has a preprocessor mode, I assume they learnt the same lesson.
The bigger lesson is that it really doesn't matter how many millions of logs you can generate per second if you don't have the infrastructure to store and analyze them easily. No one is going to enjoy digging through these things and the more you generate, the harder it is to extract meaningful information.
In other words, pay a lot more attention to what you'll do with the logs rather than how fast you can spew them out. I have rarely needed more than a few thousand log messages/sec even for a loaded MMO server. I spent way more time creating ways to look at these logs and making them accessible in near real time.