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Continuous Full GCing?

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lfisher
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Joined: 2010-11-13

Once my web application runs for awhile, it hits kind of a "wall" and gets stuck continuous full GCing. I'm not sure if it happens after a certain period of time or after a certain load. But it has been happening with 36 hours generally.
My most recent ops were
JAVA_OPTS="-server -XX:MaxGCPauseMillis=2000 -XX:PermSize=512m -XX:MaxPermSize=512m -XX:GCTimeRatio=19 -Xloggc:gclogs.txt -XX:+PrintGCTimeStamps -XX:+PrintGCDetails -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/root/heapdumps"

(I actually just reduced the starting permsize on my latest restart. It was only this week that I stopped setting all memory and started trying GCTimeRatio and MaxGCPauseMillis. It seemed really good for awhile, but still eventually got stuck doing full GCs.)
java version is
java version "1.6.0_16"
Java(TM) SE Runtime Environment (build 1.6.0_16-b01)
Java HotSpot(TM) 64-Bit Server VM (build 14.2-b01, mixed mode)

I am using CentOS with 16GB of RAM and 8 CPUs.
Thanks for any suggestions to help this.
Here is some info from the gc log.
121419.223: [Full GC [PSYoungGen: 1125632K->246286K(1152768K)] [PSOldGen: 2740223K->2740223K(2740224K)] 3865855K->2986510K(3892992K) [PSPermGen: 92307K->92307K(524288K)], 5.2961490 secs] [Times: user=5.29 sys=0.00, real=5.29 secs]
121424.777: [Full GC [PSYoungGen: 1125632K->245831K(1152768K)] [PSOldGen: 2740223K->2740223K(2740224K)] 3865855K->2986055K(3892992K) [PSPermGen: 92616K->92616K(524288K)], 5.3420100 secs] [Times: user=5.34 sys=0.00, real=5.34 secs]
121430.444: [Full GC [PSYoungGen: 1125632K->194353K(1152768K)] [PSOldGen: 2740223K->2740224K(2740224K)] 3865855K->2934577K(3892992K) [PSPermGen: 94127K->94112K(524288K)], 6.7109090 secs] [Times: user=6.71 sys=0.00, real=6.71 secs]
121437.460: [Full GC [PSYoungGen: 1125632K->253495K(1152768K)] [PSOldGen: 2740224K->2740224K(2740224K)] 3865856K->2993719K(3892992K) [PSPermGen: 95478K->95478K(524288K)], 5.3300280 secs] [Times: user=5.34 sys=0.00, real=5.33 secs]
121443.043: [Full GC [PSYoungGen: 1125632K->251341K(1152768K)] [PSOldGen: 2740224K->2740224K(2740224K)] 3865856K->2991565K(3892992K) [PSPermGen: 95791K->95791K(524288K)], 5.3263110 secs] [Times: user=5.32 sys=0.00, real=5.33 secs]
121448.620: [Full GC [PSYoungGen: 1125632K->258678K(1152768K)] [PSOldGen: 2740224K->2740224K(2740224K)] 3865856K->2998902K(3892992K) [PSPermGen: 95824K->95824K(524288K)], 5.3091370 secs] [Times: user=5.31 sys=0.00, real=5.31 secs]
121454.225: [Full GC [PSYoungGen: 1125632K->210239K(1152768K)] [PSOldGen: 2740224K->2740223K(2740224K)] 3865856K->2950463K(3892992K) [PSPermGen: 95825K->95822K(524288K)], 7.1492470 secs] [Times: user=7.15 sys=0.00, real=7.14 secs]
121461.664: [Full GC [PSYoungGen: 1125632K->278511K(1152768K)] [PSOldGen: 2740223K->2740223K(2740224K)] 3865855K->3018735K(3892992K) [PSPermGen: 95822K->95822K(524288K)], 5.3382140 secs] [Times: user=5.34 sys=0.00, real=5.34 secs]
121467.255: [Full GC [PSYoungGen: 1125632K->271135K(1152768K)] [PSOldGen: 2740223K->2740223K(2740224K)] 3865855K->3011359K(3892992K) [PSPermGen: 95823K->95823K(524288K)], 5.3244460 secs] [Times: user=5.32 sys=0.00, real=5.33 secs]

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kcpeppe
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Joined: 2003-06-15

Either resident size is greater than heap size or this is a memory leak.
Regards,
Kirk