About weak

manual

Entity Management Settings

Explains settings and performance tuning of JPA entities in ObjectDB, the fast Java object database for JPA/JDO.... = "warning" /> <cache ref = "weak" level2 = "0mb" /> <fetch hollow = "true" ... <cache> element <cache ref = "weak" level2 = "0mb" /> The <cache> element ...

 
forum_thread

Entity Management Config questions

Hi, the manual states the following regarding config of Entities: http://www.objectdb.com/java/jpa/setting/entities  : <cache ref="weak" level2="0mb" /> The <cache> element specifies settings of the two cache mechanisms for entities:... : <cache ref = "weak" level2 = "0mb" /> The <cache> element ... serves as a first level cache). The valid values are "weak" , "soft " and "strong " . Modified entities are always ... Question : What exactly is the difference between "weak", "soft", and "strong" references? ...

 
manual

Working with JPA Entity Objects

Explains the entity object lifecycle and the persistence context.... a transaction are held in the persistence context by weak references. Therefore, when a managed entity object is no longer in use by ... to use strong references or soft references instead of weak references . The contains method can check if a specified ...

 
forum_thread

Soft Reference Object Cache Recommendation

(Trying again.  Last post, ~50 minutes to compose, failed, possibly due to an attachment upload size limit being exceeded before the post attempt.  =(  ) ... on GC because this is the way soft references work (unlike weak references). ObjectDB Support ObjectDB - ... suggestions?  Perhaps setting ObjectDB to use weak references but then using persistent object callback/listeners to track ...

 
release

2.6.7

... Fixed a regression bug due to changing references to weak in 2.6.4_04 ( issue #255 ). Fixed a bug in enhancing an ... Changed references to new flushed objects from ObjectDB to weak references. Cancelled an exception on cascading removal of ...

 
release

2.6.8

... Fixed a regression bug due to changing references to weak in 2.6.4_04 ( issue #255 ). Fixed a bug in enhancing an ... Changed references to new flushed objects from ObjectDB to weak references. Cancelled an exception on cascading removal of ...

 
release

2.6.9

... Fixed a regression bug due to changing references to weak in 2.6.4_04 ( issue #255 ). Fixed a bug in enhancing an ... Changed references to new flushed objects from ObjectDB to weak references. Cancelled an exception on cascading removal of ...

 
forum_thread

PersistenceException: Failed to locate field

Hi, have recently been running into this issue when changing the schema: com.objectdb.o._PersistenceException: Failed to locate field in this case, adding a primitive String field to an Entity. pretty sure that in the past schema evolution would not have triggered errors, is this case, a simple new field, shouldn't the policy be to add a null in that field, or other default for that primitive. ... = "warning" />   <cache ref = "weak" level2 = "20m" />   <fetch hollow = "true" ... = "warning" /> <cache ref = "weak" level2 = "20m" /> <fetch hollow = "true" ...

 
issue

Use temporary files to enable very large transactions

We have transactions in which many objects are created. These objects are no longer needed in the current transaction after creation. Unfortunately, we will receive an OutOfMemory exception because the objects are kept in the first level cache of ObjectDB. In the forum thread http://www.objectdb.com/database/forum/921 on post #4 you wrote, that ObjectDB should support very large transactions in further version. Can you implement it that ObjectDB used temporary files? ... entity objects. <cache ref = "weak" level2 = "0" /> When the 2nd level cache is ... /> <cache ref = "weak" level2 = "0" /> <fetch hollow = ...

 
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: ... data structures for every persisted object, but uses weak references, so as soon as you release  your own references to ... Yes we know about WEAK REFERENCEs in ObjectDb to application entities and tried to remove all ...