Heikki Linnakangas <heikki(at)enterprisedb(dot)com> writes:
> Roger Leigh wrote:
>> PostgreSQL is using the old SYSV shared memory and semaphores, as evidenced
>> by ipcs:
> A patch to do that submitted was submitted in Spring, but it was not
> accepted for 8.3 because there was some issues with it.
More strongly: it never will be accepted because the POSIX API doesn't
offer the features we need.
You can use POSIX semaphores if you choose (there are compile options
for that), but experience to date says that that degrades performance.
POSIX shared memory is simply not happening.
regards, tom lane