I have OS X tiger with all the updates: uname -r 8.8.0 Here is what I get when I try to initdb on a freshly compiled 8.2: selecting default max_connections ... 10 selecting default shared_buffers/max_fsm_pages ... 400kB/20000 creating configuration files ... ok creating template1 database in /usr/local/pgsql/data/base/1 ... FATAL: could not create shared memory segment: Cannot allocate memory DETAIL: Failed system call was shmget(key=2, size=1646592, 03600). HINT: This error usually means that PostgreSQL's request for a shared memory segment exceeded available memory or swap space. To reduce the request size (currently 1646592 bytes), reduce PostgreSQL's shared_buffers parameter (currently 50) and/or its max_connections parameter (currently 10). The PostgreSQL documentation contains more information about shared memory configuration. child process exited with exit code 1 I read the documentation (http://www.postgresql.org/docs/8.2/static/kernel-resources.html) and added the appropriate items to /etc/sysctl.conf, and I rebooted for it to take effect. cat /etc/sysctl.conf kern.sysv.shmmax=4194304 kern.sysv.shmmin=1 kern.sysv.shmmni=32 kern.sysv.shmseg=8 kern.sysv.shmall=1024 I still get the error when I initdb. OS X and PostgreSQL has worked before for me, compiled from the source. regards, karen