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0 Replies Latest reply: May 15, 2012 6:31 AM by 716026 RSS

Frequent Old Collection - How to resize old heap size?

716026 Newbie
Currently Being Moderated
java version "1.6.0_20"
Java(TM) SE Runtime Environment (build 1.6.0_20-b02)
Oracle JRockit(R) (build R28.0.1-21-133393-1.6.0_20-20100512-2126-linux-x86_64, compiled mode)

Hi,

Observing gc output I'm seeing periodic OC kicking-in for over a ~20 min period. Can anyone explain why this is so? It seems it is too small, so how can it be resized?

e.g. Here is a excerpt from the gc log:
[INFO ][memory ] Running with 32 bit heap and compressed references supporting 32GB heap.
[INFO ][memory ] GC mode: Garbage collection optimized for throughput, strategy: Generational Parallel Mark & Sweep.
[INFO ][memory ] Heap size: 6291456KB, maximal heap size: 6291456KB, nursery size: 3145728KB.
...
[INFO ][memory ] [YC#190] 62596.929-62597.159: YC 5465974KB->3662996KB (6291456KB), 0.230 s, sum of pauses 229.234 ms, longest pause 229.234 ms.
[INFO ][memory ] [YC#191] 62626.178-62626.303: YC 5652376KB->3786644KB (6291456KB), 0.125 s, sum of pauses 121.703 ms, longest pause 121.703 ms.
[INFO ][memory ] [YC#192] 62653.547-62653.648: YC 5835966KB->3958662KB (6291456KB), 0.101 s, sum of pauses 99.949 ms, longest pause 99.949 ms.
[INFO ][memory ] [YC#193] 62680.452-62680.575: YC 5905133KB->4038661KB (6291456KB), 0.124 s, sum of pauses 123.288 ms, longest pause 123.288 ms.
*[INFO ][memory ] [OC#81] 62699.044-62704.169: OC 5323948KB->1453584KB (6291456KB), 5.125 s, sum of pauses 5097.092 ms, longest pause 5097.092 ms.*
*[INFO ][memory ] [OC#82] 62704.169-62707.777: OC 1455082KB->1300587KB (6291456KB), 3.608 s, sum of pauses 3582.001 ms, longest pause 3582.001 ms.*
*[INFO ][memory ] [OC#83] 62708.135-62712.661: OC 1325520KB->1303308KB (6291456KB), 4.527 s, sum of pauses 4380.882 ms, longest pause 4380.882 ms.*
*[INFO ][memory ] [OC#84] 62712.661-62716.163: OC 1309304KB->1301631KB (6291456KB), 3.502 s, sum of pauses 3463.554 ms, longest pause 3463.554 ms.*
*[INFO ][memory ] [OC#85] 62737.185-62741.946: OC 2864334KB->1469535KB (6291456KB), 4.761 s, sum of pauses 4715.955 ms, longest pause 4715.955 ms.*
*[INFO ][memory ] [OC#86] 62741.946-62744.593: OC 1470084KB->1306460KB (6291456KB), 2.647 s, sum of pauses 2620.734 ms, longest pause 2620.734 ms.*
*[INFO ][memory ] [OC#87] 62744.848-62749.172: OC 1310280KB->1306604KB (6291456KB), 4.324 s, sum of pauses 4195.396 ms, longest pause 4195.396 ms.*
*[INFO ][memory ] [OC#88] 62749.172-62752.511: OC 1318921KB->1305222KB (6291456KB), 3.339 s, sum of pauses 3301.721 ms, longest pause 3301.721 ms.*
*[INFO ][memory ] [OC#89] 62782.100-62788.442: OC 3521560KB->1535963KB (6291456KB), 6.342 s, sum of pauses 6176.340 ms, longest pause 6176.340 ms.*
*[INFO ][memory ] [OC#90] 62788.442-62791.821: OC 1542532KB->1317122KB (6291456KB), 3.378 s, sum of pauses 3310.585 ms, longest pause 3310.585 ms.*
*[INFO ][memory ] [OC#91] 62792.223-62796.458: OC 1333743KB->1312298KB (6291456KB), 4.236 s, sum of pauses 4097.895 ms, longest pause 4097.895 ms.*
*[INFO ][memory ] [OC#92] 62796.459-62800.685: OC 1325737KB->1309132KB (6291456KB), 4.226 s, sum of pauses 4198.279 ms, longest pause 4198.279 ms.*
*...*
*[INFO ][memory ] [OC#116] 63013.902-63016.868: OC 1324000KB->1318196KB (6291456KB), 2.966 s, sum of pauses 2938.315 ms, longest pause 2938.315 ms.*
[INFO ][memory ] [YC#194] 63051.928-63052.051: YC 3883415KB->2062914KB (6291456KB), 0.123 s, sum of pauses 121.587 ms, longest pause 121.587 ms.
[INFO ][memory ] [YC#195] 63071.064-63071.172: YC 3963008KB->2124004KB (6291456KB), 0.107 s, sum of pauses 105.896 ms, longest pause 105.896 ms.


Thanks

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