> -----Original Message----- > From: [email protected] [mailto:pgsql-admin- > [email protected]] On Behalf Of Tapio Pitkäranta > Sent: Friday, March 18, 2011 4:10 AM > To: Devrim GÜNDÜZ > Cc: [email protected] > Subject: Re: [ADMIN] Memory limits and PostgreSQL 8.4 - Over 63 GB of > memory for DB? > > Hello, > > Thank you for the reply. It seems you might be right: > > /etc/sysctl.conf > > # Controls the maximum shared segment size, in bytes > kernel.shmmax = 68719476736 > > # Controls the maximum number of shared memory segments, in pages > kernel.shmall = 4294967296 > > We have tried to set shared_buffers over 63 GB. > > Do you have any advice on memory settings for servers with large > amounts of memory (100-200GB)? It seems there is not too much > documentation on that in the net.
This is unlikely to work out as you expect. Values for shared buffers over the 8-10GB range aren't recommended. It may need to be much lower, depending on your workload. As far as recommendations - try and gauge the size of your working data set and size the shared buffers for that. From there - test with your workload, and watch out for checkpoint spikes. Unused memory will still be available to the filesystem to cache data there. Brad. -- Sent via pgsql-admin mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
