Overhead of pthread mutexes?

Question

I\'m trying to make a C++ API (for Linux and Solaris) thread-safe, so that its functions can be called from different threads without breaking internal data structures. In m

Answer 1

I did a similar library and didn't have any trouble with lock performance. (I can't tell you exactly how they're implemented, so I can't say conclusively that it's not a big deal.)

I'd go for getting it right first (i.e. use locks) then worry about performance. I don't know of a better way; that's what mutexes were built for.

An alternative for single thread clients would be to use the preprocessor to build a non-locked vs locked version of your library. E.g.:

#ifdef BUILD_SINGLE_THREAD
    inline void lock () {}
    inline void unlock () {}
#else
    inline void lock () { doSomethingReal(); }
    inline void unlock () { doSomethingElseReal(); }
#endif

Of course, that adds an additional build to maintain, as you'd distribute both single and multithread versions.