About Data Source

forum_thread

Some technical questions

Hi, ObjectDB looks interesting. Have two technical questions... (1) what locking model does ObjectDB use? I.e. 2PL or MVCC? Do writers block readers? Do readers block writers? (2) what's the recommended usage for SAAS? One ObjectDB database per customer, or one ObjectDB database for all? Thank you, Andrej ... does it implement something like MVCC, so it can see the data at the time the backup was started (to have consistent backup data)?  Thanks Andrej   ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
forum_thread

How to track memory leak with ObjectDb.

Hello, I suspect some memory leak in my application. ( turning app into OOM very fast ) In fact, some com.objectdb.o.MST objects are retaining a huge % of my heap space. While watching the dump file ( with Eclipse MAT ), i was not able to inspect carrefully the memory leak issue. That's is very hard to debug because of obfuscated objectdb code. Well, objectdb is closed source, ok so ... but, in production case, how can a developper do his debug job correctly with your obfuscated code ? ... obfuscated objectdb code. Well, objectdb is closed source, ok so ... but, in production case, how can a developper do his debug ... NB : I can't give you a dump ( too huge and some data are private )   Edit : I observed some deap objects ...

 
forum_thread

Memory Leaks after COMMIT operation (checked on versions 2.6.5 & 2.6.6.b01)

During import big logs we are observed some memory leaks inside of ObjectDb, so, could you explain what we did incorrectly or investigate how to fix it ASAP. Source code which causing memory leaks: ... did incorrectly or investigate how to fix it ASAP. Source code which causing memory leaks: m_EntityMgrFactory = ... ObjectDB allocates internal data structures for every persisted object, but uses weak references, so as ...

 
issue

Index Rebuilder

When a new index is added to an existing entity classes that already has instances in the database, it cannot be used in queries, because it starts empty and it is not synchronized with the existing primary data. The Index Rebuilder tool will enable rebuilding indexes, synchronizing their data to the primary data. As a workaround, you can currently use the ObjectDB Doctor to build a new database file, in which such new indexes will be enabled.... starts empty and unsynchronized with the existing primary data. The Index Rebuilder tool will enable rebuilding indexes, ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
issue

File lock exception on odb$

Not sure if this is an objectdb issue or not but I thought I'd raise it just in case. We had a server failure which caused an unexpected reboot. As a result, the application services which use objectdb were not shutdown properly which in turn meant we had several odb$ files left behind. I had assumed that objectdb would reprocess these when the services restarted but instead we got the exception below. ... the dbs were empty anyway but I'm a bit worried about data loss if & when this is not the case. Caused by: ... Source) at ... Source) at ... Source) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native ... Similar exceptions have been viewed in the past but the source of this issue is still unclear. Is this repeatable? i.e. can you ...

 
forum_thread

Groovy JPA example

I've been using Groovy with ObjectDb, just thought I'd post a short snippet to show how easy this is to do. The following script (which is one import and one statement) will open a database, run a query and print some results. --------------------------------------------------------------- import javax.persistence.Persistence ... have a JDBC driver, so you cannot configure a JDBC based data source. You can connect ObjectDB from Groovy as specified in #1 above, ...

 
forum_thread

Run out of memory

Hi, I've been looking into ObjectDB for our use, where everything has been great apart from I'm stuck on the following problem.   I am trying to load a large file (> 1GB), process certain information and store it back in the database to access / modify later. I require to be able to rollback changes as well, where there can be massive amount of changes.   ... massive amount of changes. I have been storing the data using a single entity manager and following the batch shown at ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
forum_thread

A few questions on object database design

I've been trying to model a database that stores data in an MMORPG. With ObjectDB, a lot of things are easier to perform. Intuitively, I created an entity class called player and stored everything about the player as embeddable classes. However, my colleague questions about this structure, since we would be looking at persisting data from the server every minute or two per player. He has stability issues with the ObjectDB if we are accessing the same table all the time.... I've been trying to model a database that stores data in an MMORPG. With ObjectDB, a lot of things are easier to perform. ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
forum_thread

Optimization Question

One of our uses for your ObjectDB software is in maintaining the current state of a large number of data objects called tracks. These tracks change very frequently over time (every 10-15 seconds is not unreasonable), but they are also very large complex data structures so it's extremely difficult to identify exactly what fields have changed from one update to the next. Currently the following sequence executes when a track update comes in: - If it’s a new track simply add it to the database.... is in maintaining the current state of a large number of data objects called tracks. These tracks change very frequently over time ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...

 
forum_thread

How to open a running db in ObjectDB Explorer?

Hi! I've just discovered that I can't see the content of a database while it's in use. Is there any way in which I could do that? It's not nice at all to close the application, copy the db in another location, start the application then finally I could explore my data, but it will be just a copy of the data, not the live information. ... start the application then finally I could explore my data, but it will be just a copy of the data, not the live information. ... block. Avoid overflow of published source code examples by breaking long lines . You may mark in ...