Fast thread syncronization

Question

I'm working on a system that have multiple threads and one shared object. There is a number of threads that do read operations very often, but write operations are rare, maybe 3 to 5 per day.

I'm using rwlock for synchronization but the lock acquisition operation it's not fast enough since it happens all the time. So, I'm looking for a faster way of doing it.

Maybe a way of making the write function atomic or looking all threads during the write. Portability it's not a hard requirement, I'm using Linux with GCC 4.6.

Answer 1

Have you considered using read-copy-update with liburcu? This lets you avoid atomic operations and locking entirely on the read path, at the expense of making writes quite a bit slower. Note that some readers might see stale data for a short time, though; if you need the update to take effect immediately, it may not be the best option for you.