If you don't care about portability, pthread_rwlocks stored in shmem should work fine. The reason we didn't implement a cross-process rwlock in APR is because we couldn't guarantee a proper implementation (at the time) on all supported platforms.
-aaron On Mon, Feb 05, 2007 at 03:44:16PM +0000, Christiaan Lamprecht wrote: > Last Nov 22 I asked a question about writable shared memory, > everything's working now so thanks! > > Locking the shared memory is turning out to be quite costly. I have > many shared-memory readers and only a few writers so using a rwlock > seems appropriate but APR provides only apr_thread_rwlock routines. > > Is there a way to use rwlocks between processes rather than threads? > Maybe using the standard POSIX pthread_rwlock routines (storing the > lock in the shm space...)? > > Many thanks again > Christiaan > > PS: > Apache 2 on Linux > apr_shm (for shared memory) > prefork MPM (it's non threaded!) >
