Management of Concurrent Clients

Hi all,

I am working on an application that involves multiple processes
accessing and updating different databases: tables are split into 3
different databases that are accessed by 3 different processes. This
architectural decision was made in the past because it has been noticed
that former revisions of postgres used to lock the whole database when a
process performs an update (on a record) which prevents the other
processes from accessing the database.

After some readings on postgres concurrent client management, I am
planning on changing the database structure to make all application
processes access a shared database (i.e. put all application tables in a
single database that would be shared among the 3 processes). I did not
find in the documentation (at least in the current versions of postgres
starting from revision 7) any specific problem related to doing this,
comments on this problem will be appreciated.

Thanks!

Hanan