Hi Tino, Thanks for your response! I did not provide more specific technical details because I just came in to the project. So, I will try to provide as much information as I can. Former versions of postgresql used in this project are postgresql (starting at 6). I will try to find out the exact revision number. It has been reported to me that the main problem encountered with former postgresql versions is that when a process performs an update (of a record in any table), the whole database was locked which prevents the other processes from accessing the database (to retrieve data for instance). In other words, the process performing the update operation had an exclusive access to the database. This had an important impact on the system performance and justified the fact that tables were spread into different databases. Usually, granularity on locks is at the row or table level but maybe there was a specific configuration that was used which made it so that the entire database was locked. Before starting any major database re-structuring, I want to make sure that are not specific cases where this situation occurs. Thanks! Hanan -----Original Message----- From: Tino Wildenhain [mailto:tino@xxxxxxxxxxxxx] Sent: Sunday, February 26, 2006 12:54 PM To: Hanan Bentaleb Cc: pgsql-general@xxxxxxxxxxxxxx Subject: Re: [GENERAL] Management of Concurrent Clients Hanan Bentaleb schrieb: > 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. Which former revision should that have been? Was it postgres95 or was it postgresql yet? > 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. Its very unclear what kind of problems you expect. Accessing postgresql with lots of clients is a common practice. You can also use schemas to isolate your applications in the same database if you need that. If you want better advice, give more details on what your application does and what exact problems you expect. Regards Tino
