Hi, I've started looking into Boost.Log as one of the possible solutions for out multi-platform project with, alas, Microsoft Windows being one of the them platforms. While the solution is multi-threaded, we are trying to avoid any thread synchronization on common resources by using sequential task queues associated with these resources. The resulting internal architecture is thus fully asynchronous with no synchronization points between worker threads. So I'm trying to fit Boost.Log into this, and the documentations, while exhaustive, still leaves some questions unanswered. Or perhaps I missed them. For instance, as far as the sources go, the library offers two logger flavors ... thread safe (I'm assuming guarded by mutex) and single threaded variants. I'm inclined towards using the latter (obviously, don't want to sync on mutex) but that would mean creating thousands of logger instances and I don't have a feeling how heavy or lightweight the logger is. Hence the first questions: 1. How heavy the logger is and what would it mean to have thousands of them around? 2. Why is there a need for _mt variants? Solely to protect logger internal data or to synchronize operations towards the core? 3. Is there anything else the loggers do apart from storing source specific attributes and associating them with the record, and serving as an open/push frontend to the core? And since the alternative is to directly use the core rather than going through the loggers, this immediately raises the next question: 4. are the following core operations internally synchronized: core::get(), core::open_record(), core::push_record()? And the final question: 5. If we were to go with using the core directly, would it be better to store shared pointer obtained via core::get() or to call core::get() for each log (basically, whether is it okay to store shared pointers to core up until the start of the end of the destruction sequence of the process? I think the sinks are more thoroughly covered in the docs. I'm unsure at the moment whether to use one of those already available in the library with the asynchronous frontend, or go for the unlocked frontend with the own backend associated with the task queue. While I'm aware I did not provide enough information to directly ask the question, any thoughts on this would nevertheless be welcome. Thank you and best regards, Leon