Setting kernel memory for installing postgresql
- by Matthieu Taymans
My question is about setting the kernel shared memory for installing postgresql on mac osx 10.6.8. In the readme file of postgresql it is said:
Shared Memory
PostgreSQL uses shared memory extensively for caching and
inter-process communication. Unfortunately, the default configuration
of Mac OS X does not allow suitable amounts of shared memory to be
created to run the database server.
Before running the installation, please ensure that your system is
configured to allow the use of larger amounts of shared memory. Note
that this does not 'reserve' any memory so it is safe to configure
much higher values than you might initially need. You can do this by
editting the file /etc/sysctl.conf - e.g.
% sudo vi /etc/sysctl.conf
On a MacBook Pro with 2GB of RAM, the author's sysctl.conf contains:
kern.sysv.shmmax=1610612736 kern.sysv.shmall=393216 kern.sysv.shmmin=1
kern.sysv.shmmni=32 kern.sysv.shmseg=8 kern.maxprocperuid=512
kern.maxproc=2048
Note that (kern.sysv.shmall * 4096) should be greater than or equal to
kern.sysv.shmmax. kern.sysv.shmmax must also be a multiple of 4096.
Once you have edited (or created) the file, reboot before continuing
with the installation. If you wish to check the settings currently
being used by the kernel, you can use the sysctl utility:
% sysctl -a
The database server can now be installed.
I'm a real beginner with all this but need to instal postgresql for academic purposes do you know how i can set this kernel shared memory. Won't that be harmful for my system?
Thank you in advance.
Matthieu
