[JENA-181] Fuseki starts producing 500 errors if rapidly sent a sequence of queries

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Not a Problem
• Affects Version/s: Fuseki 0.2.1
• Component/s: Fuseki

Environment

Mac OS X Lion

• Assignee: Andy Seaborne
• Reporter: Rob Vesse
• Created: 19/Dec/11 17:30
• Updated: 21/Dec/11 11:31
• Resolved: 20/Dec/11 12:25

Description

It is fairly trivial to cause Fuseki to start generating a 500 : Direct buffer memory error code in response to queries simply by sending a sequence of queries to it with no delays between them, even with a short delay e.g. 0.5 seconds Fuseki will typically get into this state at a similar point.

Attached is a simple test case which fires SELECT * WHERE { } queries at a local Fuseki instance, for me this reliably fails on the 25th iteration, turning on --debug and --verbose for Fuseki and modifying the log4j.properties file to set DEBUG level for everything didn't show anything particularly useful on the command line so I have no idea what the cause of this may be beyond something related to java.nio.HeapByteBuffer