Caching primitive array types consumes excessive memory

• Key: OPENJPA-71
• Type: Bug
• Status: Resolved
• Resolution: Fixed
• Priority: Major
• Assignee: Unassigned
• Reporter: Roger Keays
• Component/s: datacache
• Affects Version/s: 0.9.0, 0.9.6
• Fix Version/s: 0.9.7

Description

As reported on the mailing list: http://www.nabble.com/cached-byte---consumes-excessive-memory-tf2543098.html , in org.apache.openjpa.AbstractPCData#toData() an ArrayList is used to cache all types of arrays, including arrays of primitives. This can use excessively large amounts of memory because of the wrappers required for each element in the array. In one test case, a 7MB byte[] consumed 127MB when converted to a cached ArrayList.

AbstractPCData needs to be fixed to handle simple arrays.

Comments

[Patrick Linskey]

What happens if openjpa.DynamicDataStructs is enabled?

Resolved. I changed AbstractPCData to not marshal / unmarshal arrays via Lists, but I did not do any memory footprint measurement.