Thread Safety

This library is not designed to be thread-safe.

However, it should be safe to use one lcb_INSTANCE object per thread, with some caveats and careful consideration.

1. You must be certain that the lcb_INSTANCE is not shared with other threads. For performance, there are no internal locks or other thread safety mechanisms to protect internal data structures.
2. Also for performance reasons, the default logger is not thread-safe, and is not bound to a single lcb_INSTANCE. Therefore, a multi-threaded application must also override the logger with a thread-safe version or use a separate logger for each instance (see example example/threads-private/threads-private.c).
3. Likewise, any other shared instances that are registered with the library (e.g., lcb_io_opt_t) must also be protected in a similar manner. Such instances must either be protected and made thread-safe internally or a new instance per lcb_INSTANCE can be provided.

As with any multi-threaded application extra testing and analysis should be done using a tool like Valgrind/DRD, ThreadSanitizer or similar.

• example/threads-shared/threads-shared.c - this example shows how to protect single lcb_INSTANCE when it is shared between multiple threads.
• example/threads-private/threads-private.c - this example shows how to bind lcb_INSTANCE to each thread, and how to use custom logger in the thread-safe way.