libGL.so is thread safe. The overhead of thread safety for common,
single-thread clients is negligible. However, the overhead of thread
safety for multi-threaded clients is significant. Each GL API call
-requires two calls to pthread_get_specific() which can noticably
+requires two calls to pthread_get_specific() which can noticeably
impact performance. Warning: libGL.so is thread safe but individual
DRI drivers may not be. Please consult the documentation for a driver
to learn if it is thread safe.