FULL PRODUCT VERSION :
java version "1.6.0_01"
Java(TM) SE Runtime Environment (build 1.6.0_01-b06)
Java HotSpot(TM) 64-Bit Server VM (build 1.6.0_01-b06, mixed mode)

FULL OS VERSION :
SunOS z20000c.ningops.com 5.10 Generic_118855-33 i86pc i386 i86pc

A DESCRIPTION OF THE PROBLEM :
We're getting a segmentation fault in the GC thread about once every 1-2 hours in a long-running server process.

These are our current JVM settings:

-server
-XX:+HeapDumpOnOutOfMemoryError
-XX:+UseConcMarkSweepGC
-XX:+DisableExplicitGC
-XX:CMSInitiatingOccupancyFraction=1
-XX:+UseCMSInitiatingOccupancyOnly
-XX:MaxNewSize=170M
-XX:MaxTenuringThreshold=15
-Xmx1800m
-Xms1800m

These settings used to work well, though:

-server
-XX:NewSize=256M
-XX:+UseConcMarkSweepGC
-XX:+CMSIncrementalMode
-XX:+DisableExplicitGC
-XX:+HeapDumpOnOutOfMemoryError
-Xmx1792m
-Xms1792m


THE PROBLEM WAS REPRODUCIBLE WITH -Xint FLAG: Did not try

THE PROBLEM WAS REPRODUCIBLE WITH -server FLAG: Yes

ERROR MESSAGES/STACK TRACES THAT OCCUR :
see attachment

REPRODUCIBILITY :
This bug can be reproduced often.