Andrew Dunstan wrote:
> I don't understand how we decide that everybody who needs a given > event+message has got it, if we don't know who (if anyone) is listening? > How do we decide that we no longer need the info in the shmem buffer? Keep a pointer in shared memory for each listener backend, saying how far it has scanned the ring? There would be a single writing pointer, so it's trivial to see when the ring is "full". > Timeout? sinval issues a reset if the buffer becomes full, but we can't > do that here. Just have NOTIFY block when the buffer is full, and maybe issue a warning so that the user knows that he should increase the ring size. > Are we keeping use of SIGUSR2 in this scheme? What for? Just protect the write pointer with a lwlock and have listeners check whether somebody has written something. ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
