Full GC runs even when enough space is remaining
I am running a server application with these specs:
OS: Solaris 9 32-bit
JVM: 1.4.2_11
Xms=Xmx=2048M
GC Settings:
-Xmn=256M
-XX:+UseParNewGC
-XX:+UseConcMarkSweepGC
-XX:PermSize=32M
-XX:MaxPermSize=128M
-XX:SurvivorRatio=8
-XX:MaxTenuringThreshold=36
-XX:+UseCMSCompactAtFullCollection
-XX:CMSFullGCsBeforeCompaction=0
What I am seeing is Full GC runs 2-3 times even when sufficient tenured and young generation space is available and I don't understand why. Can someone please help?
2704.556: [CMS-concurrent-mark: 19.951/20.159 secs]
2704.556: [CMS-concurrent-preclean-start]
2705.262: [CMS-concurrent-preclean: 0.702/0.706 secs]
2705.263: [GC2705.263: [Rescan (parallel) , 0.2308587 secs]2705.494: [weak refs processing, 0.0025950 secs] [1 CMS-remark: 1297867K(1835008K)] 1323674K(2070976K), 0.2339031 secs]
2705.497: [CMS-concurrent-sweep-start]
2711.955: [Full GC {Heap before GC invocations=325:
Heap
par new generationtotal 235968K, used 88220K [0x70c00000, 0x80c00000, 0x80c00000)
eden space 209792K, 36% used [0x70c00000, 0x756d6c28, 0x7d8e0000)
from space 26176K, 44% used [0x7f270000, 0x7fdc0540, 0x80c00000)
tospace 26176K,0% used [0x7d8e0000, 0x7d8e0000, 0x7f270000)
concurrent mark-sweep generation total 1835008K, used 1297793K [0x80c00000, 0xf0c00000, 0xf0c00000)
concurrent-mark-sweep perm gen total 32768K, used 20306K [0xf0c00000, 0xf2c00000, 0xf8c00000)
2711.956: [ParNew: 88220K->15915K(235968K), 0.0430720 secs]2711.999: [CMS2713.816: [CMS-concurrent-sweep: 8.143/8.320 secs]
(concurrent mode failure)[Unloading class sun.reflect.GeneratedConstructorAccessor26]
[Unloading class sun.reflect.GeneratedConstructorAccessor46]
[Unloading class sun.reflect.GeneratedConstructorAccessor29]
[Unloading class sun.reflect.GeneratedConstructorAccessor30]
[Unloading class sun.reflect.GeneratedConstructorAccessor27]
[Unloading class sun.reflect.GeneratedConstructorAccessor52]
[Unloading class sun.reflect.GeneratedSerializationConstructorAccessor1]
[Unloading class sun.reflect.GeneratedConstructorAccessor55]
[Unloading class sun.reflect.GeneratedConstructorAccessor56]
[Unloading class sun.reflect.GeneratedConstructorAccessor54]
[Unloading class sun.reflect.GeneratedConstructorAccessor51]
[Unloading class sun.reflect.GeneratedConstructorAccessor58]
[Unloading class sun.reflect.GeneratedConstructorAccessor42]
[Unloading class sun.reflect.GeneratedConstructorAccessor57]
[Unloading class sun.reflect.GeneratedConstructorAccessor41]
[Unloading class sun.reflect.GeneratedConstructorAccessor40]
[Unloading class sun.reflect.GeneratedConstructorAccessor25]
[Unloading class sun.reflect.GeneratedConstructorAccessor48]
[Unloading class sun.reflect.GeneratedConstructorAccessor21]
[Unloading class sun.reflect.GeneratedConstructorAccessor49]
[Unloading class sun.reflect.GeneratedConstructorAccessor47]
[Unloading class sun.reflect.GeneratedConstructorAccessor20]
[Unloading class sun.reflect.GeneratedConstructorAccessor50]
[Unloading class sun.reflect.GeneratedMethodAccessor6]
[Unloading class sun.reflect.GeneratedConstructorAccessor24]
[Unloading class sun.reflect.GeneratedConstructorAccessor28]
[Unloading class sun.reflect.GeneratedConstructorAccessor53]
[Unloading class sun.reflect.GeneratedMethodAccessor1]
: 1297793K->1313434K(1835008K), 44.4053374 secs] 1386013K->1313434K(2070976K), [CMS Perm : 20306K->20216K(32768K)] Heap after GC invocations=326:
Heap
par new generationtotal 235968K, used 0K [0x70c00000, 0x80c00000, 0x80c00000)
eden space 209792K,0% used [0x70c00000, 0x70c00000, 0x7d8e0000)
from space 26176K,0% used [0x7d8e0000, 0x7d8e0000, 0x7f270000)
tospace 26176K,0% used [0x7f270000, 0x7f270000, 0x80c00000)
concurrent mark-sweep generation total 1835008K, used 1313434K [0x80c00000, 0xf0c00000, 0xf0c00000)
concurrent-mark-sweep perm gen total 33696K, used 20216K [0xf0c00000, 0xf2ce8000, 0xf8c00000)
} , 44.4809014 secs]
2756.750: [GC [1 CMS-initial-mark: 1313434K(1835008K)] 1316446K(2070976K), 0.0188777 secs]
2756.769: [CMS-concurrent-mark-start]
2758.999: [Full GC {Heap before GC invocations=326:
Heap
par new generationtotal 235968K, used 29273K [0x70c00000, 0x80c00000, 0x80c00000)
eden space 209792K, 13% used [0x70c00000, 0x72896560, 0x7d8e0000)
from space 26176K,0% used [0x7d8e0000, 0x7d8e0000, 0x7f270000)
tospace 26176K,0% used [0x7f270000, 0x7f270000, 0x80c00000)
concurrent mark-sweep generation total 1835008K, used 1313434K [0x80c00000, 0xf0c00000, 0xf0c00000)
concurrent-mark-sweep perm gen total 33696K, used 21369K [0xf0c00000, 0xf2ce8000, 0xf8c00000)
2759.000: [ParNew: 29273K->983K(235968K), 0.0133278 secs]2759.014: [CMS2777.123: [CMS-concurrent-mark: 20.209/20.353 secs]
(concurrent mode failure): 1313434K->1313732K(1835008K), 60.4770959 secs] 1342707K->1313732K(2070976K), [CMS Perm : 21369K->21364K(33696K)] Heap after GC invocations=327:
Heap
par new generationtotal 235968K, used 0K [0x70c00000, 0x80c00000, 0x80c00000)
eden space 209792K,0% used [0x70c00000, 0x70c00000, 0x7d8e0000)
from space 26176K,0% used [0x7f270000, 0x7f270000, 0x80c00000)
tospace 26176K,0% used [0x7d8e0000, 0x7d8e0000, 0x7f270000)
concurrent mark-sweep generation total 1835008K, used 1313732K [0x80c00000, 0xf0c00000, 0xf0c00000)
concurrent-mark-sweep perm gen total 35608K, used 21364K [0xf0c00000, 0xf2ec6000, 0xf8c00000)
} , 60.4921313 secs]
Message was edited by:
tsriram07
Message was edited by:
tsriram07
