db4o Developer Community

Hello,

I'd like to know how much data can be put into the db4o-database (Java version)? I read something about 16GB, is this true?

I plan to use it for a project where lots of data (several GB) have to be stored withing a short amount of time (as fast as possible), so Multithreading is another issue.

I played a bit around and found out that Multithreading works quite fine when using the DB as server (opening the file via method #openServer()), are there any other possibilities?

Thank you and best regards,
Snappsen

Hi,

MoleHillRocker:

I'd like to know how much data can be put into the db4o-database (Java version)? I read something about 16GB, is this true?

no, it's 254GB per database-file...

http://developer.db4o.com/Resources/view.aspx/Reference/Tuning/Performance_Hints/Increasing_The_Maximum_Database_File_Size

MoleHillRocker:

I plan to use it for a project where lots of data (several GB) have to be stored withing a short amount of time (as fast as possible), so Multithreading is another issue.

I played a bit around and found out that Multithreading works quite fine when using the DB as server (opening the file via method #openServer()), are there any other possibilities?

The db4o-core is thread-safe, so you can run db4o in "embedded" mode also which usually gives you the best performance (no overhead for c/s-communication). db4o uses a "universal global lock" internally to synchronize all database-access (regardless if used embedded or C/S), so C/S will give you no performance gain.

I would suggest to benchmark db4o with a typical data-set. There are lots of hints regarding performance tuning which depend largely on your object-model. For a general reading have a look at:

http://developer.db4o.com/Resources/view.aspx/Reference/Tuning/Performance_Hints

Cheers, Maik