Thread: max_connections
Hi all,
I am using postgres 8.3.9 on SUSE 64 bit. By default max_connections is 100, but I want to know if this can be increased, if so, what should we take into consideration?
Thank you,
Sireesha
On Wed, Sep 5, 2012 at 2:30 PM, Modumudi, Sireesha <Sireesha.Modumudi@emc.com> wrote: > Hi all, > > I am using postgres 8.3.9 on SUSE 64 bit. By default max_connections is 100, > but I want to know if this can be increased, if so, what should we take into > consideration? If you're considering raising this then you should probably be looking at some kind of pooler like pgbouncer or pgool. That said I've run servers that did things like sessions (small transactions and lots of idle connects) to ~1000 before but make sure you've got enough memory free as each backend will use about 6MB of memory.
"Modumudi, Sireesha" <Sireesha.Modumudi@emc.com> wrote: > I am using postgres 8.3.9 on SUSE 64 bit. By default > max_connections is 100, but I want to know if this can be > increased, if so, what should we take into consideration? http://wiki.postgresql.org/wiki/Number_Of_Database_Connections -Kevin
According to http://www.postgresql.org/docs/8.3/static/kernel-resources.html The maximum shared memory usage of a connection in bytes is 1800 + 270 * max_locks_per_transaction max_locks_per_transaction default is 64 19080 Bytes or .018 mb's per connection or 1.819 mb at 100 default connections With a Gig of Phsical Ram setting Shared Buffers to use 25% - 256 mb dedicated to Postgres default is using roughly 0.75% for connections You can extrapolate this out taking into consideration all your specific variables, total physical RAM, postgresql.conf settings etc but I wouldn;t run off to use pgpool unless your in an extremly connection heavy environment as it does add an additional layer within the client server connection and is another component to config and admin. -- View this message in context: http://postgresql.1045698.n5.nabble.com/max-connections-tp5722890p5722899.html Sent from the PostgreSQL - general mailing list archive at Nabble.com.
Sireesha Modumudi wrote: > I am using postgres 8.3.9 on SUSE 64 bit. By default max_connections is 100, but I want to know if > this can be increased, if so, what should we take into consideration? It can be increased, but you habe to restart the server for the change to take effect. It is not a good idea to increase the setting without thought. There is a Wiki article about it: http://wiki.postgresql.org/wiki/Number_Of_Database_Connections If you need more than 100 connections, consider the use of a connection pool. Yours, Laurenz Albe