On 05/22/2013 02:41 AM, Geert Wirken wrote:
The default is good for most people. For small setups, it extra load of having a DB session handler doesn't really matter, and for large setups, you probably want the DB session handler because you would like to share session information amongst all your webserver nodes. That's quite a reasonable default. Go ahead and modify RC if you would like to use an alternative session handler, but most admins won't be interested in using it.
One of the common costs of using a db is the additional disk I/O. If you're using MySQL, you could set the sessions table to use ENGINE=MEMORY:
https://dev.mysql.com/doc/refman/5.5/en/memory-storage-engine.html
Or if you're using Postgres, you could use an UNLOGGED table:
http://www.postgresql.org/docs/9.1/static/sql-createtable.html#AEN67496
Both of these approaches should significantly reduce the I/O overhead for the sessions table (though at the cost of losing sessions in the event of a power failure or other unclean shutdown), while keeping the same sessions table trivially visible for all connecting web frontends, since they already all have access to the database.
Regards,
--dkg